(12.7)
2. A swimming pool is in the shape of a rectangular
prism with a horizontal cross-section 10 feet by 20
feet. The pool is 5 feet deep and filled to capacity.
Water has a density of approximately 60 pounds
per cubic foot
What is the approximate mass of water in the pool?
A. 8,000 lb.
B.
12,500 lb.
C
16,700 lb.
D. 60,000 lb.

The velociraptor's speed is 2 m/s, and its velocity is -0.3 m/s [w].

To calculate the speed and velocity of the velociraptor, we need to first find the total distance it covered and the displacement.

Total distance = 5m + 10m + 3m + 2m = 20m

Displacement = Final position - Initial position

Displacement = (2m [w]) - (5m [e])

Displacement = -3m [w]

Velocity is defined as displacement per unit time, while speed is defined as distance per unit time.

Velocity = Displacement / Time

Velocity = -3m [w] / 10s

Velocity = -0.3 m/s [w]

Speed = Total distance / Time

Speed = 20m / 10s

Speed = 2 m/s

Therefore, the velociraptor's speed is 2 m/s, and its velocity is -0.3 m/s [w].

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The value of the account is 1.05 times as large as the previous year

There is a 2-column table with 6 rows representing the value of a savings account at the end of each year for 6 years. The relationship between the years and the value of the account is exponential, and there is a rate of change in this exponential relationship.

To find the rate of change in this exponential relationship, you can follow these steps:

1. Divide the value of the account in the second year by the value of the account in the first year: 5,512.50 / 5,250 = 1.05.

2. Since the relationship is exponential and the rate of change is constant, the account's value will increase by the same factor every year. In this case, the rate of change is 1.05, which means that after each year, the value of the account is 1.05 times as large as the previous year.

In summary, the rate of change in the exponential relationship between the increasing years and the increasing value of the account is 1.05, meaning that after each year, the value of the account is 1.05 times as large as the previous year.

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The area of the panel left after she cuts the hole is 5.215 ft²

Given that a circular hole of 1 foot by foot has been cut out of a rectangular panel of 3 feet by 2 feet,

We need to find the area of the remaining part after the cutting of the hole,

So, we will find the same by subtracting the area of the hole from the area of the panel.

So, area of the hole = π×radius² = 3.14×0.5² = 0.785 ft²

Area of the panel = length × width = 3 × 2 = 6 ft²

Area remaining part = 6-0.785 = 5.215 ft²

Hence the area of the panel left after she cuts the hole is 5.215 ft²

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Properties B and C together ensure that there exists a 'c' in (-1, 1) at which f'(c) = 0.
Your answer: 1. B and C only

Which properties ensure that there exists ?

a 'c' in (-1, 1) at which f'(c) = 0, given f(-1) = f(1) = and the properties A, B, and C.

First, let's define the properties:
f(1) = 2
f is continuous on (-1, 1]
f(x) = (22/3) - x^2

To ensure that there exists a 'c' in (-1, 1) at which f'(c) = 0, we will use the Mean Value Theorem (MVT). MVT states that if a function is continuous on a closed interval and differentiable on an open interval, then there exists at least one 'c' in the interval where the derivative is 0.

Looking at property B, it states that f is continuous on (-1, 1], which satisfies the first condition of the MVT. Property C provides a specific function for f(x), which is differentiable on (-1, 1) since it is a polynomial function. Therefore, properties B and C together ensure that there exists a 'c' in (-1, 1) at which f'(c) = 0.

Your answer: 1. B and C only

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Answer:

0.91

30.4

850

Step-by-step explanation:

The coordinates of the triangle after the dilation are given as follows:

a(0, 12), b(-6, 15) and c(9, 21).

The perimeter of the triangle increases, as the side lengths are multiplied by 3, hence the perimeter is also multiplied by 3.

A dilation can be defined as a transformation that multiplies the distance between every point in an object and a fixed point, called the center of dilation, by a constant factor called the scale factor.

The scale factor for this problem is given as follows:

k = 3.

The scale factor is greater than 1, meaning that the figure is an enlargement, and thus the perimeter increases.

The original vertices of the triangle are given as follows:

a(0, 4), b(−2, 5), and c(3, 7)

Hence the vertices of the dilated triangle are given as follows:

a(0, 12), b(-6, 15) and c(9, 21).

(each coordinate of each vertex is multiplied by the scale factor of 3).

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The length of AC in triangle ABC is 24 inches.

In triangle ABC, let point D be on side AC such that AB = BD = DC = 12 inches. We are given that the measure of angle BDC is twice the measure of angle ABD.

To find the length of AC, we can use the Law of Cosines. This law relates the lengths of the sides of a triangle to the cosine of one of its angles. In this case, we can apply the Law of Cosines to triangle ABD to find the length of AD:

AD^2 = AB^2 + BD^2 - 2 * AB * BD * cos(ABD)

Since AB = BD = 12 inches, we have:

AD^2 = 12^2 + 12^2 - 2 * 12 * 12 * cos(ABD)

AD^2 = 288 - 288 * cos(ABD)

Now, let's consider triangle BDC. We are given that the measure of angle BDC is twice the measure of angle ABD. Let's denote the measure of angle ABD as x. Therefore, the measure of angle BDC is 2x.

Since the sum of angles in a triangle is 180 degrees, we can write:

x + 2x + angle BCD = 180

3x + angle BCD = 180

angle BCD = 180 - 3x

Now, let's apply the Law of Cosines to triangle BDC to find the length of BC:

BC^2 = BD^2 + CD^2 - 2 * BD * CD * cos(BDC)

BC^2 = 12^2 + 12^2 - 2 * 12 * 12 * cos(2x)

BC^2 = 288 - 288 * cos(2x)

Since AD = DC, we have AD = 12 inches. Now we can write the equation for the total length AC:

AC = AD + DC

AC = 12 + 12

AC = 24 inches

Therefore, the length of AC in triangle ABC is 24 inches.

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Able Cable offers the fastest mean downloading speed among the three providers with a speed of 4.0 Mbps.

We can calculate the mean (average) download speed for each provider and compare them to determine which company offers the fastest mean downloading speed.

Based on the given data, the mean download speed for each provider is:

City Net: (3.6 + 3.7 + 3.7 + 3.6 + 3.9) / 5 = 3.7 megabits per second (Mbps)

Able Cable: (3.9 + 3.9 + 4.1 + 4.0 + 4.1) / 5 = 4.0 Mbps

Tel-N-Net: (3.9 + 3.7 + 4.0 + 3.6 + 3.8) / 5 = 3.8 Mbps

Therefore, Able Cable offers the fastest mean downloading speed among the three providers with a speed of 4.0 Mbps.

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To solve this problem, we need to use related rates. Let's start by drawing a diagram:

```
        /\
       /  \
      /    \
     /      \
    /        \
   /__________\
```

We know that the radius of the conical pile is always two times its height, so we can label the diagram as follows:

```
        /\
       /  \
      /    \
     /      \
    /        \
   /__________\
  /|    r=2h   \
 / |___________\
```

Now we need to find an equation that relates the height of the pile to its radius. We can use the formula for the volume of a cone:

```
V = (1/3)πr^2h
```

We want to solve for h in terms of r:

```
V = (1/3)πr^2h
3V/πr^2 = h
```

Now we can differentiate both sides of this equation with respect to time:

```
d/dt (3V/πr^2) = d/dt h
0 = (3/πr^2) dV/dt - (2/πr^3) dr/dt
```

We're given that the height is increasing at a rate of 2 cm/s when the pile is 11 cm high, so we know that:

```
dh/dt = 2 cm/s
h = 11 cm
```

We want to find the rate at which sand is leaving the bin, which is given by `dV/dt`. We can solve for this using the equation we derived:

```
0 = (3/πr^2) dV/dt - (2/πr^3) dr/dt
dV/dt = (2/3)πr^2 (dh/dt) / r
```

Now we just need to plug in the values we know:

```
dh/dt = 2 cm/s
h = 11 cm
r = 2h = 22 cm

dV/dt = (2/3)π(22)^2 (2) / 22
dV/dt = 264π/3
```

So the rate at which sand is leaving the bin when the pile is 11 cm high is `264π/3 cm^3/s`.

To solve this problem, we can use the relationship between the radius and height of the conical pile, as well as the given rate of height increase.

Since the radius (r) is always two times the height (h), we have r = 2h. The volume (V) of a cone is given by the formula V = (1/3)πr^2h. We can substitute r with 2h, so V = (1/3)π(2h)^2h.

Now, let's differentiate both sides with respect to time (t):

dV/dt = (1/3)π(8h^2)dh/dt

When the height is 11 cm, the rate of height increase (dh/dt) is 2 cm/s. We can substitute these values into the equation:

dV/dt = (1/3)π(8(11)^2)(2)

Solving for dV/dt:

dV/dt ≈ 2046.92 cm³/s

At that instant, the sand is leaving the bin at a rate of approximately 2046.92 cm³/s.

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To test the claim that the outcomes of rolling the modified die are not equally likely, we can use a chi-square goodness-of-fit test. We will use a significance level of 0.05.

The null hypothesis is that the outcomes are equally likely. The alternative hypothesis is that the outcomes are not equally likely.

First, we need to calculate the expected frequencies assuming that the outcomes are equally likely.

Since the die has six sides, each outcome has a probability of 1/6. Therefore, the expected frequency for each outcome is 200/6 = 33.33.

To calculate the test statistic [tex]x^2[/tex], we can use the formula:

[tex]x^2 = Σ (observed frequency - expected frequency)^2 / expected frequency[/tex]

where Σ is the sum over all outcomes.

Using the observed and expected frequencies given in the problem, we get:

[tex]x^2 = (27 - 33.33)^2 / 33.33 + (31 - 33.33)^2 / 33.33 + (42 - 33.33)^2 / 33.33 + (40 - 33.33)^2 / 33.33 + (28 - 33.33)^2 / 33.33 + (32 - 33.33)^2 / 33.33[/tex]

[tex]x^2 = 3.02[/tex]

The degrees of freedom for this test is 6 - 1 = 5 (since there are 6 sides on the die).

Using a chi-square distribution table (or calculator), we can find the critical value for a significance level of 0.05 and 5 degrees of freedom to be 11.070.

Since the test statistic x^2 = 3.02 is less than the critical value of 11.070, we fail to reject the null hypothesis.

Therefore, we do not have enough evidence to conclude that the outcomes of rolling the modified die are not equally likely.

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the answer is Q1 = 27.5

The correct answer is option (d) (x, y) → (x + 1/3, y + 1/3).

The dilation is a type of transformation that changes the size of the object, but not the shape. It can be represented by a rule in which each point of the original object is multiplied or divided by a constant factor. In this case, since the center of dilation is the origin, we can find the constant factor by dividing the coordinates of the corresponding points of the two rectangles.

Let's take the point Q(x, y) in rectangle QRST and its corresponding point Q'(x', y') in rectangle Q'R'S'T'. Since the dilation is centered at the origin, we have:

x' = k * x

y' = k * y

where k is the constant factor of dilation. We can find k by dividing the corresponding sides of the rectangles. For example, the length of QR is 4 units, and the length of Q'R' is 4/3 units. Therefore, k = 4/3.

Using this value of k, we can find the coordinates of any point in rectangle QRST that corresponds to a point in rectangle Q'R'S'T'. For example, point R(6, 2) in rectangle QRST corresponds to point R'(6 + 1/3, 2 + 1/3) = (20/3, 7/3) in rectangle Q'R'S'T'.

Hence, the correct answer is (x, y) → (x + 1/3, y + 1/3).

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The decay of the radioactive substance can be modeled by the exponential decay function:

y = a(1 - r)^t

where:

- y is the amount of substance present after t hours

- a is the initial amount of substance (in grams), which is 120 grams in this case

- r is the decay rate per hour, which is 18% or 0.18 in decimal form

- t is the time elapsed in hours

Plugging in the values we get:

y = 120(1 - 0.18)^t

Simplifying:

y = 120(0.82)^t

So this is the equation that represents the number of grams, y, present after t hours, given the initial amount of 120 grams and a decay rate of 18% per hour.

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A sequence of transformations that maps figure 1 onto figure 2 and then figure 2 onto figure 3 include the following: D. a translation followed by a rotation.

In Mathematics and Geometry, a translation can be defined as a type of rigid transformation which moves every point of the object in the same direction, as well as for the same distance.

This ultimately implies that, a translation is a type of rigid transformation  that does not change the orientation of the original geometric figure (pre-image).

In Mathematics, a rotation is a type of transformation which moves every point of the object through a number of degrees around a given point, which can either be clockwise or counterclockwise (anticlockwise) direction.

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Complete Question:

Which sequence of transformations maps figure 1 onto figure 2 and then figure 2 onto figure 3?

a reflection followed by a translation

a rotation followed by a translation

a translation followed by a reflection

a translation followed by a rotation

If Ann takes a boat then the distance between Ann's home and the market across the lake is approximately 29 km.

To find the distance from Ann's home to the market, we can use the Pythagorean theorem, which states that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.

In this case, Ann's home, the market, and the point where she crosses the lake form a right triangle, with the distance she travels across the lake being the hypotenuse.

To calculate the distance, we can use the following formula:

c^2=a^2+b^2

where c is the distance from Ann's home to the market, a is the distance from her home to the point where she crosses the lake, and b is the distance from the market to the point where she crosses the lake.

We know that a = 20 km and b = 21 km, so we can plug these values into the equation:

c^2=20^2+21^2

c^2=400+441

c^2=841

To solve for c, we take the square root of both sides of the equation:

c=sqrt(841)

c=29

Therefore, the distance from Ann's home to the market is approximately 29 km, when she takes the shortest path across the lake directly toward the market.

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The circle's x value will continue to be the same as the arc ST. So, x has a value of 40 degrees.

A circle's centre is the point from which all of the distances to the other points on the circle are equal. The radius of the circle is the measurement at issue.

Every point on a circle is a geometric shape that is equally separated from the centre.

The location of any point that is evenly separated from the fixed point known as the circle's centre can also be characterised as it.

The distance from any point on a circle to the centre is known as the radius of the circle.

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Answer:

Add the lengths:

5x - 16 + 2x - 4 = 7x - 20

Therefore, the value of x to the nearest hundredth is approximately 72.73 units.

A triangle is a geometrical shape that consists of three straight sides and three angles. It is a polygon with three vertices, and the sum of its interior angles always adds up to 180 degrees. Triangles are classified based on the length of their sides and the measure of their angles. The most common types of triangles are equilateral, isosceles, and scalene, based on the length of their sides, and acute, right, and obtuse, based on the measure of their angles. Triangles have a wide range of applications in mathematics, physics, engineering, and other fields.

Here,

Therefore, in this triangle, sin(67°) = 67/x, where x is the length of the hypotenuse.

We can rearrange this equation to solve for x:

x = 67 / sin(67°)

Using a calculator, we find that sin(67°) is approximately 0.921, so:

x = 67 / 0.921

x ≈ 72.73

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Answer:

a) £54

b) £1908

Step-by-step explanation:

a) use £1800 × 3% = £54

b) use £1800 + ( 54 × 2) = £1908

The volume of the table tent 3 cmH8 cm12 cm is 288 cubic cm.

The volume of the table tent can be found by multiplying the length, width, and height of the tent.

Volume = length x width x height

In this case, the length is 12 cm, the width is 8 cm, and the height is 3 cm.

Volume = 12 cm x 8 cm x 3 cm

Volume = 288 cubic cm

Therefore, the volume of the table tent is 288 cubic cm.

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She would have to work for 11 hours to pay these bills without her FSA/HSA.

Emma went to the doctor 9 times last month, which means she had to pay a total of 9 x $20 = $180 in copays.

Without her FSA/HSA, she would have to work to earn $180 after taxes. Since she pays 17 percent in taxes, the amount she would have to earn before taxes is $180 / (1 - 0.17) = $216.87.

To earn $216.87, she would have to work for $216.87 / $20 per hour = 10.84 hours.

Rounding up, she would have to work for 11 hours to pay these bills without her FSA/HSA.

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Answer:

The total area of the "t" figure is 20 square units.

The figure is made up of a triangle, a square, and a rectangle.

The area of the triangle is (1/2)(base)(height) = (1/2)(4)(3) = 6 square units.

The area of the square is 4^2 = 16 square units.

The area of the rectangle is 2(4)(3) = 24 square units.

The total area of the figure is 6 + 16 + 24 = 46 square units.

However, the question asks for the area of the composite region, which is the shaded region in the figure. The shaded region is a triangle with base 4 units and height 3 units. The area of this triangle is (1/2)(base)(height) = (1/2)(4)(3) = 6 square units.

Therefore, the area of the composite region is 6 square units.

Here is a diagram of the figure with the areas of each shape labeled:

[Image of the "t" figure with the areas of each shape labeled]

Answer:

Step-by-step explanation:

I don't have enough information to answer this.

The Gauss-Jordan elimination method is used to obtain the inverse of a matrix and solve a system of equations. The solution for the given system is x1 = 2/3, x2 = 5/3, x3 = 2/3.

We can represent the given system of equations in the matrix form as

| 4   3   1 |   | x1 |   | 2 |

| 1   1   1 | * | x2 | = | 3 |

| 2   5   2 |   | x3 |   | 1 |

Let's perform Gauss-Jordan elimination to obtain the inverse of the matrix A.

Augment the matrix with an identity matrix of the same order:

| 4   3   1 |   | 1  0  0 |   | ? ? ? |

| 1   1   1 | * | 0  1  0 | = | ? ? ? |

| 2   5   2 |   | 0  0  1 |   | ? ? ? |

Use row operations to transform the left side of the augmented matrix into an identity matrix:

| 4   3   1 |   | 1  0  0 |   | ? ? ? |   | 1  0  0 |

| 1   1   1 | * | 0  1  0 | = | ? ? ? | =>| 0  1  0 |

| 2   5   2 |   | 0  0  1 |   | ? ? ? |   | 0  0  1 |

To achieve this, we can subtract 2 times the second row from the third row, and subtract 4 times the second row from the first row:

| 4   3   1 |   | 1  0  0 |   | ? ? ? |   | 1  0  0 |

| 1   1   1 | * | 0  1  0 | = | ? ? ? | =>| 0  1  0 |

| 0   3   0 |   | 0 -2  1 |   | ? ? ? |   | 0  0  1 |

Next, we can divide the second row by 3 to obtain a leading 1 in the second row, and subtract 3 times the second row from the first row:

| 1   0  -1 |   | 1 -1  1/3 |   | ? ? ? |   | 1  0  0 |

| 0   1  0  | * | 0  1  0   | = | ? ? ? | =>| 0  1  0 |

| 0   0  1  |   | 0 -2  1   |   | ? ? ? |   | 0  0  1 |

Finally, we can add the third row to the first row and subtract the third row from the second row

| 1   0  0 |   | 1 -1  4/3 |   | ? ? ? |   | 1  0  0 |

| 0   1  0 | * | 0  1  2   | = | ? ? ? | =>| 0  1  0 |

| 0   0  1 |   | 0 -2  1   |   | ? ? ? | =>| 0  0  1 |

Hence, we have obtained the inverse of the matrix A as

| 1 -1  4/3 |

| 0  1  2   |

| 0 -2  1   |

We can now find the solution vector x by multiplying the inverse of A with the vector b

| x1 |   | 1 -1  4/3 |   | 2 |

| x2 | = | 0  1  2   | * | 3 |

| x3 |   | 0 -2  1   |   | 1 |

Performing the matrix multiplication, we get

| x1 |   | 2/3 |

| x2 | = | 5/3 |

| x3 |   | 2/3 |

Therefore, the solution of the given system of equations is

x1 = 2/3

x2 = 5/3

x3 = 2/3

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The daily newspaper has the most users among those surveyed.

To determine which news source has the most users, we need to compare the percentages of those who use each source.

According to the survey:

55% get news from local television station

60% get news from daily newspaper

40% get news from the internet

To compare these percentages, we can either convert them to fractions or decimals. Let's convert them to decimals:

55% = 0.55

60% = 0.60

40% = 0.40

Now we can compare them directly. We see that the source with the highest percentage is the daily newspaper, with 60% of those surveyed saying they get news from it. Therefore, the daily newspaper has the most users among the surveyed population.

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The value of KL as shown in the image is 12 units

An equation is an expression that shows how numbers and variables using mathematical operators.

Two triangles are said to be similar, if the ratio of their corresponding sides are in the same proportion.

For the triangle shown, since triangle XYZ is similar to triangle JKL, hence:

KL/XY  = KJ / XZ

substituting, KJ = 10.44:

KL / 8.7 = 11.31 / 8.2

KL = 12

The value of KL is 12 units

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The factored form of the polynomial x⁴ - 2x³- 16x² + 2x + 15 is [x³(x - 2) - (4x + 3)(4x - 5)].

Factoring the polynomial?

x⁴- 2x³ - 16x² + 2x + 15.

First, look for any common factors among the terms. In this case, there are none.

Next, try factoring by grouping. To do this, group the first two terms and the last three terms: (x⁴ - 2x³) - (16x² - 2x - 15).

Factor out the greatest common factor from each group: x³(x - 2) - 1(16x² - 2x - 15).

Now, we have a difference of two expressions, but there isn't a common factor to factor further. Therefore, we must use other methods to factor the quadratic expression 16x²- 2x - 15.

Factor the quadratic expression using the "ac method." Multiply the leading coefficient (16) by the constant term (-15) to get -240. Find two numbers that multiply to -240 and add up to the linear coefficient (-2). These numbers are 12 and -20.

Rewrite the middle term using the two numbers found: 16x² + 12x - 20x - 15.

Group the terms in pairs: (16x² + 12x) + (-20x - 15).

Factor out the greatest common factor from each group: 4x(4x + 3) - 5(4x + 3).

Factor out the common binomial factor: (4x + 3)(4x - 5).

Now, put everything together: x³(x - 2) - (4x + 3)(4x - 5).

So, the factored form of the polynomial x⁴ - 2x³- 16x² + 2x + 15 is [x³(x - 2) - (4x + 3)(4x - 5)].

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The combination of these side lengths uniquely determines the shape of the triangle.

Hi! To draw a triangle with side lengths 3 inches, 5 inches, and 6 inches, make sure that the sum of any two sides is greater than the third side. In this case, 3 + 5 > 6, 3 + 6 > 5, and 5 + 6 > 3, so a triangle can be formed.

Yes, this is the only triangle you can draw using these side lengths.

The reason is that the side lengths are fixed, and according to the triangle inequality theorem, the combination of these side lengths uniquely determines the shape of the triangle.

The combination of these side lengths uniquely determines the shape of the triangle.

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The value of measure of RU is,

⇒ 149°

We have to given that;

In circle,

m RS = 88 degree

m ST = 35 degree

Hence, We can formulate;

The value of measure of RU is,

⇒ 360° - ( 88° + 35° + 88°)

⇒ 360° - 211°

⇒ 149°

Thus, The value of measure of RU is,

⇒ 149°

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Answer:

3. 254.34 mm^2

4. 615.44 cm^2

5. 314 in^2

6. 7.065 in^2

7. 3.14 cm^2

8. 1.76625 ft^2

Step-by-step explanation:

AREA FORMULA: π * r^2

This question is asking to use 3.14 or 22/7 for x.

The following steps will use 3.14.

3. r = 9 mm (r^2 = 81 mm)

A = 81 * 3.14 = 254.34 mm^2

4. r = 14 cm (r^2 = 196 cm)

A = 196 * 3.14 = 615.44 cm^2

5. r = 10 in (r^2 = 100 in)

A = 100 * 3.14 = 314 in^2

Questions 6-8 show the diameter of the circle.

Divide by 2 to find the radius, then plug that into the area formula

6. r = 1.5 in (r^2 = 2.25 in)

A = 2.25 * 3.14 = 7.065 in^2

7. r = 1 cm (r^2 = 1 cm)

A = 1 * 3.14 = 3.14 cm^2

8. r = 0.75 ft (r^2 = 0.5625 ft)

A = 0.5625 * 3.14 = 1.76625 ft^2