the area of a certain state is 840000 square miles. what is this area in scientific notation?
1. 8.4x10.-4
2. 84x10.-3
3. 84x10.3
4. 8.4x10.5
please help

The solution to the system of equations is:

e = 0.109

g = 0.183

Defining the variables:

g = cost of the unit of gas.

e = cost of the unit of electricity.

Then the system of equations is:

150*g + 520*e = 84.20

210*g + 405*e = 82.35

Now we want to solve this.

To do so, we need to isolate one of the variables in one of the equations. Let's isolate g in the first one:

g = (84.20 - 520*e)/150

Now we replace that in the other equation so we get:

210*(84.20 - 520*e)/150 + 405*e = 82.35

Now we can solve this for e:

210*(84.20 - 520*e)/150 + 405*e = 82.35

(210/150)*(84.20 - 520*e) + 405*e = 82.35

117.6 - 728*e + 405*e = 82.35

117.6  - 323*e = 82.35

e = (117.6  - 82.35)/323 = 0.109

Then:

g = (84.20 - 520*0.109)/150 = 0.183

Then we can conclude that:

e = 0.109

g = 0.183

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Answer: [tex]-1 \frac{19}{24}[/tex]

Step-by-step explanation:

5/6 + (−2 5/8)=

5/6 + (−2 - 5/8)=

5/6 −2 - 5/8=

(5/6 −2 - 5/8)*24/24=      ==> 24 is the LCM of 6 and 8

[tex]\frac{(5*24/6 -2*24-5*24/8)}{24}[/tex]=

[tex]\frac{(120/6 -48-120/8)}{24}[/tex]=

[tex]\frac{(20-48-15)}{24}[/tex]=

(-28-15)/24=

-43/24 =

(-24-19)/24=

-24/24 -19/24=

-(24/24 +19/24)=[tex]-1 \frac{19}{24}[/tex]

The square root of - 10 is not a real number but a complex number, an irrational number.

Numbers can be classified in real numbers and complex numbers. Real numbers are classified in natural numbers (i.e. 1, 4, 5), whole numbers (i.e. 0, 1, 4, 5), integers (i.e. - 4, -1, 0, 5, 6) and rational numbers (i.e. 5 / 7, 0, - 13 / 3) and part of the irrational numbers (i.e. √3, π) and the rest of irrational numbers are complex numbers (i.e. i 4, - 4 + i 5).

In consequence, the square root of - 10 is not a real number but a complex number, an irrational number.

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Answer:

£27400

Step-by-step explanation:

The original salary of x.

The raise was 7.5% = 7.5/100 = 0.075 of the salary.

The original salary plus the raise is x + 0.075x = 1.075x.

The new salary is £29455.

Therefore,

1.075x = £29455

Divide both sides by 1.075.

x = £27400

Answer: £27400

Answer:

3/4 or 0.75

Step-by-step explanation:

8-4x=2x

-4x-2x=-8

-6x=-8

x=-6/-8

=3/4 or 0.75

Answer:

No solution!

Step-by-step explanation:

I just took the quiz and got 100%

Answer:

- 1 makes the equation true

Step-by-step explanation:

2s - 10 = - 12 ( isolate the term in s by adding 10 to both sides )

2s = - 2 ( divide both sides by 2 )

s = - 1

The integer ion in the solution set will make the equation true is -1. The correct option is a.

Zero, a positive natural number, or a negative integer denoted by a minus sign are all examples of integers. The inverse additives of the equivalent positive numbers are the negative numbers.

An integer, pronounced "IN-tuh-jer," is a whole number that can be positive, negative, or zero and is not a fraction. Any positive or negative number without fractions or decimal places is known as an integer, often known as a "round number" or "whole number."

Given equation is

2s - 10 = - 12 ( isolate the term in s by adding 10 to both sides )

2s = - 2 ( divide both sides by 2 )

s = - 1

Therefore, the correct option is a, −1.

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Answer:

3 1/2 subtracted from 4 7/8 is equal to 3/8.

A fraction is a quantity that is not a non-integer. A fraction usually has a numerator and a denominator. The numerator is the number above. While the denominator is the number below. An example of a fraction is 1/2.

A mixed number is a number that has a whole number and a proper fraction. A proper fraction is a fraction is which the numerator is less than the denominator. An example of a mixed number is 3 1/2.

Subtraction is the mathematical operation that is used to determine the difference of two or more numbers. The sign used to represent subtraction is -.

[tex]3\frac{1}{2} - 4\frac{7}{8}[/tex]

[tex]-1\frac{4 - 7}{8}[/tex]

[tex]-1\frac{-3}{8}[/tex] = 3/8.

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So far, he has ridden 70% of the bike course.

Percentage, which was adapted from the Latin word "per centum", which means "by the hundred", is a fraction or a ratio in which the value of whole is always 100. It is represented by the symbol "%".

The formula to get the percentage is:

Percentage = (Value / Total Value) × 100

If the total value of the bike course is 40 miles and the value which the percentage we are looking for is 28 miles, evaluating the equation:

Percentage = (Value / Total Value) × 100

Percentage = (28 / 40) × 100

Percentage = (0.7) × 100

Percentage = 70

Therefore, he has ridden 70% of the bike course so far.

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Answer:

x = -2

Step-by-step explanation:

5x - 5 = 9x + 3

- 5 = 4x + 3

- 8 = 4x

- 8/4 = 4x/4

x = -2

The value of the expression when x = 7 is 70

Algebraic expressions are expressions made up of variables, terms, coefficients, factors and constants.

They are also made up of mathematical operations such as addition, multiplication, division, subtraction, etc.

Given the expression;

2x^2- 5x - 3

To determine the the value, we substitute the value of x a 7 into the expression, we have;

2(7)² - 5(7) - 3

expand the bracket

2(49) - 25 - 3

98 - 25 - 3

Find the difference

70

Thus, the value of the expression when x = 7 is 70

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The standard deviation of the distribution = 1.5°F

Given that the distribution of daily high temperature is approximately normal.

Population mean, [tex]\mu[/tex] = 86°F

Also approximately 95% of all daily high temperatures are between 83°F and 89°F.

So here [tex]X_1[/tex] = 83°F and [tex]X_2[/tex] = 89°F

We have the z - statistic ,

             [tex]z=\frac{x-\mu}{\sigma}[/tex]

where [tex]\sigma[/tex] is the Standard deviation.

For 95% probability, the z-value for normal distribution is 1.96.

As we consider the positive z-value, take X =  [tex]X_2[/tex] =  89°F

So,   [tex]z=\frac{x-\mu}{\sigma}[/tex]

⇒  [tex]\sigma = \frac{x-\mu}{z} = \frac{89-86}{1.96} =1.53[/tex] ≈ 1.5°F

So the standard deviation of the distribution = 1.5°F

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The height of this cone is 3( 1 +  [tex]\frac{l}{r}[/tex] ). Which have the same volume and surface area.

Given that

The value of the surface area (in square centimeters) of the cone is equal to the value of the volume (in cubic centimeters) of the cone.

The formula for the surface area S of a right cone is S=πr2+πrl, where r is the radius of the base and l is the slant height.

To find

The height of the cone.?

So, according to the question

We have,

The surface area of the cone = The volume of the cone.

We know that

The surface area of the cone,

  S = πr²+πrl

And,

The volume of the cone,

 V = [tex]\frac{1}{3} \pi r^2h[/tex]

So, from question

The surface area of the cone = The volume of the cone

  S = V              

Now, put the all values,

 πr²+πrl =  [tex]\frac{1}{3} \pi r^2h[/tex]

πr(r+ l)  =  [tex]\frac{1}{3} \pi r^2h[/tex]

 (r+l) =  [tex]\frac{1}{3}[/tex] × [tex]\frac{\pi r^2h}{\pi r}[/tex]

 (r+l) =  [tex]\frac{1}{3}[/tex] × rh

 [tex]\frac{3(r+l)}{r}[/tex] = h

  h = 3( [tex]\frac{r}{r} + \frac{l}{r}[/tex] )

   h = 3( 1 +  [tex]\frac{l}{r}[/tex] )

So the height of this cone is 3( 1 +  [tex]\frac{l}{r}[/tex] ).

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Answer:

[tex](f + g)( \times ) = { \times }^{4} [/tex]

1-  if the main coefficient isn't always 1, divide each facets by way of the coefficient so that the resulting equation has a leading coefficient of 1.

2- write the equation within the form ax²+ bx = c

3- write the left aspect of the equation because the rectangular of a binomial and simplify the proper side if possible.

4- add the rectangular of half of the coefficient of the linear time period to both aspects of the equation.

5- practice the rectangular root property for equation and solve as usual.

What do you mean by quadratic?

Quadratics can be defined as a polynomial equation of a second degree, which means that it incorporates a minimum of one time period that is squared. it's also referred to as quadratic equations. the general shape of the quadratic equation is: ax² + bx + c = 0.

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Denominator: The value in a fraction that appears below the fractional bar and indicates the total number of equal parts.

In a fraction, the value that appears above the horizontal line is referred to as the numerator. It represents the number of pieces removed from the whole. The denominator of a fraction is the numerical value that comes before the vinculum.

A mixed number is a representation of both a whole number and a legal fraction. In most cases, it denotes a number that falls between any two whole numbers.

An integer that totally or partially divides another integer is known as a divisor.

In a division equation, a divisor is represented by the formula

Dividend ÷ Divisor = Quotient.

The correct option is (a).

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Ratios which are not equivalent to 3: 5 are 13: 15, 7:9, 5:3.

As given in the question,

Mo is sorting number cards with ratios

Ratio = 3 : 5

Equivalent ratio to 3 : 5

13 : 15 cannot be reduced.

13 : 15 not equivalent to 3:5

30:50 = (3 ×10) : (5×10)

          = 3:5

7:9  cannot be reduced . It is not equivalent to 3:5

3x:5x = 3:5

5:3 reciprocal of 3:5 .It is not equivalent to 3:5.

Therefore, ratios which are not equivalent to 3: 5 are 13: 15, 7:9, 5:3.

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The required equation would be t  = (nRT + 5ab)/M which is the result of the equation for t.

The equation is defined as mathematical statements that have a minimum of two terms containing variables or numbers that are equal.

The equation is given as

Mt - 5ab = nRT

We have to determine the result of solving this equation for t

⇒ Mt - 5ab = nRT

⇒ Mt  = nRT + 5ab

⇒ t  = (nRT + 5ab)/M

Therefore, the required equation would be t  = (nRT + 5ab)/M which is the result of the equation for t.

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Answer:

9

Step-by-step explanation:

a quotient is the result of dividing one number by the other, so we know 8 is being divided by 2

8÷2 is 4

five more just means adding 5

so we are left with 4+5 which =9

The number 0.1875 is a Rational number.

What is Rational number?

If a number can be expressed as a fraction of two integers then its called Rational number.

Given that;

The number = 0.1875

Now, Determine if it is rational or not we can convert it into fraction as;

0.1875 = 1875/10000

Divide numerator and denominator by 25,

= 75/400

Again, Divide numerator and denominator by 25,

= 3/16

Clearly, The above is a rational number because it can be expressed as a fraction of two integers.

So, The number 0.1875 is a Rational number.

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Answer:

answer of the first one

x+1>3 equal to x>2 by subtracting 1 from each side

so x>2 equal ]2,infinity[

answer of the second

-4<x<2 so the quantity of x is all the numbers from -4 to 2 but when it be greater than or smaller than without saying or equal we put the brackets opened so the result is ]-4,2[

but i can,t understand 3 and 4

Answer: are there any options?

Step-by-step explanation:

Answer:

200 km/hr

Step-by-step explanation:

We can find the speed by dividing the distance by the time taken for the trip.

[tex]\sf \boxed{Speed = \dfrac{distance }{time}}[/tex]

 [tex]\sf r = \dfrac{300}{t}[/tex]

In the above equation, substitute t = 1.5 hours and find the train's rate.

[tex]\sf r = \dfrac{300}{1.5}\\\\= \dfrac{300*10}{1.5*10}\\\\= \dfrac{3000}{15}\\\\r = 200 \ kilometers \ per \ hour[/tex]

Answer:

A. 25h+30=80

B.25(2)+30=80

After the translation the coordinates of L' are (-3, 0) for the new triangle of U’M’L’.

The coordinates of triangle are-

U (-3, -4), M(-1, -1) , and L(-2, -5).

The triangle is translated 5 units up and 1 unit left to its original place.

Thus, for the 5 units up translation 5 units will get added to the y-coordinates.

New y-coordinate of L' is -5 + 5 = 0.

For 1 unit left , 1 units will get reduced from the original x-coordinate.

New x-coordinate = -2 - 1 = -3

Thus, the new coordinates L' becomes (-3, 0).

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Answer:

-3n+12

Step-by-step explanation:

Term to term rule:

9-6=3

6-3=3

3-0=3

term to term rule is -3

-3 x n + 9 - (-3)

-3n + 12