How many times does the graph cross the x-axis for this equation y = -2x2 + 4x -
5? *

Answer:

C

Step-by-step explanation:

using Pythagoras' identity in the right triangle.

the square on the hypotenuse is equal to the sum of the squares on the other 2 sides.

let x be the hypotenuse , then

x² = 7² + 8² = 49 + 64 = 113 ( take square root of both sides )

x = [tex]\sqrt{113}[/tex]

Answer:

+5.5

Step-by-step explanation:

Lets say you have an apple and you apply -5.5 newtons of force to it, for it to be balanceds you have to push the opposite, which is +5.5 newtons.

Answer:

x = - 11

Step-by-step explanation:

[tex]\frac{-x+10}{3}[/tex] = 7 ( multiply both sides by 3 to clear the fraction )

- x + 10 = 21 ( subtract 10 from both sides )

- x = 11 ( multiply both sides by - 1 )

x = - 11

4

2x +2x +1 =13 + x

4x - x = 13 - 1

3x = 12

x=12/3

x=4

Checking, 2*4+2*4+1 =17

13+4=17

Answer:

Step-by-step explanation:

2x + 2x + 1 = 13 + x

To find the value of x, isolate 'x'

Step1: Subtract x from both sides

2x + 2x - x + 1 = 13

Step 2: Subtract 1 from both sides

2x + 2x - x  = 13 - 1

Step3: Combine like terms

       3x   = 12

Step 3: Divide both sides by 3

          x = 12/3

x = 4

Answer:

Step-by-step explanation:

You need to find the equivalent of 54 by solving and finding the root of it.

GIVEN:

2*3³

3³=27

2*27=54

Change to square root.

[tex]\sf{\sqrt{2*3^3}}[/tex]

Use the exponent rule.

EXPONENT RULE:

[tex]\Longrightarrow: \sf{\:A^{B+C}=A^B\cdot \:A^C}}[/tex]

[tex]\Longrightarrow: \sf{\sqrt{2\cdot \:3^2\cdot \:3}}[/tex]

[tex]\sf{\sqrt{2\cdot \:3^2\cdot \:3}=\sqrt{3^2}\sqrt{2\cdot \:3}}[/tex]

[tex]\Longrightarrow: \sf{\sqrt{3^2}=3}[/tex]

[tex]\sf{3\sqrt{2*\:3}}[/tex]

Then, you multiply the numbers from left to right.

2*3=6

SOLUTIONS:

[tex]\Longrightarrow: \boxed{\sf{3\sqrt{6}}}[/tex]

I hope this helps. Let me know if you have any questions.

Answer:

AC

Step-by-step explanation:

sin C = opp/hyp

For angle C, the opposite leg is AB. The hypotenuse is AC.

sin C = AB/AC

Answer:

Step-by-step explanation:

Sin of an angle refers to the ratio between the opposing side and the hypotenuse.

Answer:

x=14

Step-by-step explanation:

3x+1 and 43 are both vertical angles so they are equivant.

3x+1=43

3x=42

x=14

Using the normal distribution, it is found that the replacement time that separates the top 18% from the bottom 82% is of 11.23 years.

The z-score of a measure X of a normally distributed variable with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex] is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

In this problem, the mean and the standard deviation are, respectively, given by [tex]\mu = 9.4, \sigma = 2[/tex].

The desired value is the 82nd percentile, which is X when Z = 0.915, hence:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]0.915 = \frac{X - 9.4}{2}[/tex]

X - 9.4 = 0.915(2)

X = 11.23

The replacement time that separates the top 18% from the bottom 82% is of 11.23 years.

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Answer:£1.8Step-by-step explanation:2kg apples and 7kg pears = £12.701 kg pear costs £1.307 kg pear costs £(1.30×7)=£9.12 kg apples costs £(12.70-9.1)=£3.61kg apples cost £(3.6÷2)=£1.8

The measure of the angles are: ∠1  = 30°, ∠2  = 30°, ∠3 = 21°, ∠4 = 39°, ∠5 = 39°, ∠6 = 24°, ∠7 = 24°, ∠8 = 66°, ∠9 = 66°, ∠10 = 21°,  ∠11 = 60°, ∠12 = 120°, ∠13 = 60°, ∠14 = 120°, ∠15 = 48°, ∠16 = 105°, ∠17 = 27°, ∠18 = 129°, ∠19 = 51°, ∠20 = 129° and ∠21 = 51°

The given parameters are:

AB = 78°

FE = 105°

ED = 27°

CD = 42°

Considering the semicircle ABCD, the measure of arc BC is:

BC = 180 - AB - CD

This gives

BC = 180 - 78 - 42

Evaluate

BC = 60°

Considering the semicircle A FED, the measure of arc A F is:

A F = 180 - FE - ED

This gives

A F = 180 - 105 - 27

Evaluate

A F = 48°

The angle 16 subtends arc FE.

So, we have:

∠16 = FE

This gives

∠16 = 105°

Similarly, the angles 15 and 17 subtend arcs A F and ED respectively.

So, we have:

∠15 = 48°

∠17 = 27°

Angles at the circumference are half the angles at the arc.

This means that:

∠1 = Arc BC/2

∠3 = Arc CD/2

∠4 = Arc AB/2

∠5 = Arc AB/2

∠6 = Arc A F/2

∠10 = Arc CD/2

So, we have:

∠1 = 60/2 = 30°

∠3 = 42/2 = 21°

∠4 = 78/2 = 39°

∠5 = 78/2 = 39°

∠6 = 48/2 = 24°

∠10 = 42/2 = 21°

The angle in a semicircle is 90 degrees.

This means that:

∠2 = 90°

The sum of angles in a triangle is 180 degrees.

This means that:

∠11 = 180 - ∠1 - ∠2

∠12 = 180 - ∠3 - ∠4

So, we have:

∠11 = 180 - 30 - 90 = 60°

∠12 = 180 - 21 - 39 = 120°

Vertical angles are equal.

So, we have:

∠13 = ∠11

∠14 = ∠12

This gives

∠13 = 60°

∠14 = 120°

The sum of angles in a triangle is 180 degrees.

This means that:

∠18 = 180 - ∠17 - ∠6

So, we have:

∠18 = 180 - 27 - 24 = 129°

Vertical angles are equal.

So, we have:

∠20 = ∠18

This gives

∠20 = 129°

Angle on a straight line equals 180°.

So, we have:

∠21 = 180 - ∠18

This gives

∠21 = 180 - 129° = 51°

Vertical angles are equal.

So, we have:

∠19 = ∠21

This gives

∠19 = 51°

The sum of angles in a triangle is 180 degrees.

This means that:

∠7 = 180 - ∠21 - ∠16

So, we have:

∠7 = 180 - 51 - 105

∠7 = 24°

The angle in a semicircle is 90 degrees.

This means that:

∠7 + ∠8 = 90°

So, we have:

24 + ∠8 = 90°

Subtract 24 from both sides

∠8 = 66°

The sum of angles in a triangle is 180 degrees.

This means that:

∠8 = 180 - ∠15 - ∠9

So, we have:

∠8 = 180 - 48 - 66

So, we have:

∠8 = 66°

Hence, the measure of the angles are:

∠1  = 30°, ∠2  = 30°, ∠3 = 21°, ∠4 = 39°, ∠5 = 39°, ∠6 = 24°, ∠7 = 24°, ∠8 = 66°, ∠9 = 66°, ∠10 = 21°,  ∠11 = 60°, ∠12 = 120°, ∠13 = 60°, ∠14 = 120°, ∠15 = 48°, ∠16 = 105°, ∠17 = 27°, ∠18 = 129°, ∠19 = 51°, ∠20 = 129° and ∠21 = 51°

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Answer: $95

Step-by-step explanation:

Te new price will be 90 + 5x, if the price increases "x" times

The number of wind chimes sold per month will become 140 - 7x

[tex]\begin{aligned}&\text {Revenue, } \mathrm{R}(\mathrm{x})=(90+5 \mathrm{x})(140-7 \mathrm{x}) \\&R^{\prime}(x)=5(140-7 x)-7(90+5 x) \\&R^{\prime}(x)=700-35 x-630-35 x \\&R^{\prime}(x)=70-70 x=0 \\&70 x=70 \\&x=1\end{aligned}[/tex]

Therefore, if the price becomes (90 + 5(1)) = $95 per wind chime, then the revenue will be maximum

Answer:

c

Step-by-step explanation:

Answer: 47

Step-by-step explanation:

Rate in hours /week = 705/ 15

Answer: C=2πr

Step-by-step explanation:

Answer:

9 cm.

Step-by-step explanation:

We are given that the area of a circle is 81π cm2. 81 π c m 2 . Hence the radius of the given circle is 9 cm.

Answer:

c. 14.4

Step-by-step explanation:

when your divide 271.4^3 by 1000 you get 7.2 and then you multiply that by  2 and get 14.4 as your answer.

[tex]\begin{array}{llll} \textit{Logarithm of exponentials} \\\\ \log_a\left( x^b \right)\implies b\cdot \log_a(x) \end{array}~\hfill \begin{array}{llll} \textit{Logarithm of rationals} \\\\ \log_a\left( \frac{x}{y}\right)\implies \log_a(x)-\log_a(y) \end{array} \\\\\\ \begin{array}{llll} \textit{logarithm of factors} \\\\ \log_a(xy)\implies \log_a(x)+\log_a(y) \end{array} \\\\[-0.35em] ~\dotfill[/tex]

[tex]\log_3\left( \cfrac{18}{25} \right)\implies \log_3(18)~~ - ~~\log_3(25)\implies \log_3(2\cdot 3\cdot 3)~~ - ~~\log_3(5^2) \\\\\\\ [\log_3(2)+\log_3(3)+\log_3(3)]~~ - ~~2\log_3(5) \\\\\\\ [\log_3(2)+1+1]~~ - ~~2\log_3(5)\implies 2+\log_3(2)-2\log_3(5)[/tex]

Answer:

28 tiles in 85 minutes

1 tile in 3 minutes

Step-by-step explanation:

Figure out how long it takes Meg to lay one tile - 50 / 15 - 3.33 minutes per tile

This suggests that Jessica should take less than 3.33 mins to lay one tile for the statement to be correct.

If she lays 20 tiles in 85 minutes, it will take her 85 / 20 = 4.25 minutes per tile, so it can't be this one.

If she lays 24 tiles in 85 minutes, it will take her 85 / 24 = 3.5416 minutes per tile, so it can't be this one.

If she lays 28 tiles in 85 minutes, it will take her 85 / 28 = 3.0357 minutes per tile, so it can be this one.

If she lays 1 tile in 3 minutes, it will take her 3 / 1 = 3 minutes per tile, so it can be this one.

If she lays 1 tile in 4 minutes, it will take her 4 / 1 = 4 minutes per tile, so it can't be this one.

:)

The measure of the angle ∠DEF is 85 degrees and the measure of the angle ∠CFE is 57 degrees.

It is a polygon that has four sides. The sum of the internal angle is 360 degrees.

In a cyclic quadrilateral, the sum of opposite angles is 180°.

∠DCE + ∠DEF = 180°

             ∠DEF = 180° - ∠DCF

             ∠DEF = 180° - 95°

             ∠DEF = 85°

Similarly for the other two angles, we have

∠CDE + ∠CFE = 180°

             ∠CFE = 180° - ∠CDE

             ∠CFE = 180° - 123°

             ∠CFE = 57°

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Answer:

the interest owed is 1684.8

Step-by-step explanation:

Formula for simple interest =

I = Prt, where P is amount borrowed, r for interest rate and t for time.

Since the first three years is 1.6% interest we can write:

I = 15600 x 0.016 x 3

= 748.8

Then for the following 3 years the interest rate is 2%:

I = 15600 x 0.02 x 3

= 936

Adding the values gives us 1684.8

The mathematical mistake that Riley made is that:
"She used the wrong common denominator." (Option A)

A common denominator is a factor that is similar to all the fractions in the sequence of equations.

Hence the correct answer is:

(2(2x² - 6x + 9))/((x-3) (x-2) (x+3))

See the correct sequence of steps below:

Step One - the Expression is given as:

(x/(x-3)(x-2)) + (3/(x+3))

Step 2 - Find the common denominator and rewrite the expression so that the numerators are above the common denominators.

Hence we have:  (x (x+3) + 3(x-3) (x-2))/(x-3)(x-2)(x+3)

Step 3  Apply the Law of Multiplicative Distribution:

Hence we have  (x² +3x+3x²-9x-6x+16)/(x-3)(x-2)(x+3)

Step 4 -  Collect Like Items

This gives us: (x²+3x²)+(3x-9x-6x)+18/(x-3)(x-2)(x+3)

Step 5 Sort for like coefficients

This gives us:  ((1+3)x² +(3-9-6) * x + 18)/(x-3)(x-2)(x+3)

Step 6 -  check for the sum or difference

This gives us: (4x²+(3-9-6) * x+ 18)/(x-3)(x-2)(x+3)

We simplify and factor the expression to get

(2(2x²-6x+6)/(x-3)(x-2)(x+3).

See the attached for full question.

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Answer:

She used the wrong common denominator.

Step-by-step explanation:

Answer:

400 entries (i think that's the answer)

The maximum height is the highest level of height an object can reach. . The greatest height of the hangar is 32feet

The maximum height is the highest level of height an object can reach. Given the height in feet of the curved roof of an aircraft hangar can be modeled by y=-0.02x^2+1.6x

The velocity of the aircraft is zero at the maximum height. Therefore:

dy/dx = -0.04x + 1.6  = 0

Determine the value of x

0.04x = 1.6
x = 1.6/0.04
x = 40

Substitute x = 40 into the function to get the greatest height

y=-0.02x^2+1.6x

y=-0.02(40)^2+1.6(40)

y = -32 + 64

y = 32ft

Hence the greatest height of the hangar is 32feet

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Answer:

the answer is 980 hope this helps

a. Area of the exposed water of the prism pool: 33.5 ft²

b. The area of exposed water for the cone pool = 102.1 ft²

c. Hemisphere pool = πr² = π(4²) = 50.3 ft²

Volume = (2/3)πr

Volume = 1/3πr²h

Volume = Base area × height

a. Area of the exposed water = area of the square top = base area of the prism

Find base area using, Volume = Base area × height. Thus:

134 = Base area × 4

Base area = 134/4 = 33.5 ft²

Area of the exposed water for the prism pool = 33.5 ft²

b. Find the radius of the cone using, volume = 1/3πr²h.

134 = 1/3πr²(4)

(3)(134) = πr²(4)

402/4π = r²

32 = r²

r = 5.7 ft

The area of exposed water for the inverted cone pool = πr² = π(5.7)² = 102.1 ft²

c. The radius is the depth of the hemisphere pool

The area of the exposed water for the hemisphere pool = πr² = π(4²) = 50.3 ft²

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Answer:

1. angle addition postulate

2. angle addition postulate

3. given

4. substitution

5. given

6. substitution

7. subtraction property of equality

Answer:

A

Step-by-step explanation:

I had this same question on a quiz the other day

Answer:

B or 5 and 1/2

Step-by-step explanation:

Answer:

The answer is B. 5 1/2

Step-by-step explanation:

8 5/8 - 3 1/8 = ?

The first thing to check for, is that the fractions have the same denominator!

They do: 8

8 5/8 - 3 1/8 = 5 4/8 reduce

5 1/2.  

5 1/2 is your answer!

The question is an illustration of combination, and there are 1820 ways to select the 12 students

The distribution of the students is given as:

Senior = 7

Junior = 5

Sophomore = 4

The total number of students is:

Total = 7 + 5 + 4

Evaluate

Total = 16

To select 12 students from the 16 students, we make use of the following combination formula

Ways = 16C12

Evaluate the expression using a calculator

Ways = 1820

Hence, there are 1820 ways to select the 12 students

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Answer:

Answer A is correct

Step-by-step explanation:

Formula to find the volume of a cylinder is :

Volume = π r² h

Given that,

radius ⇒ 8 units

height ⇒ 7 units

Let us find it now.

Volume =  π r² h

Volume = π × 8 × 8 × 7

Volume = π × 64 × 7

Volume = π × 448

Volume = 448 π units³

Answer:

car and van 602

Step-by-step explanation:

brain liest me please need

There are 427 vans and 435 cars were washed.

An equation is an expression that shows the relationship between two or more numbers and variables.

A mathematical equation is a statement with two equal sides and an equal sign in between. An equation is, for instance, 4 + 6 = 10. Both 4 + 6 and 10 can be seen on the left and right sides of the equal sign, respectively.

We are given that school car wash charged $5 for a car and $6 for a van.

The total of 86 cars and vans were washed on the weekend and they earned $475.

The equation are;

x + y = 86

5x + 6y = 475

Now we have;

5x + 6y = 475

5(86- y) + 6y = 475

y = 435

Therefore,

435 + x= 8

x = - 427

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