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3 years ago

If an area of the rectangle below is 39 square feet, sides are x-2 and x+8 find the area of x

Mathematics

1 answer:

Anna71 [15]3 years ago

4 0

Answer:

x = 5.

Step-by-step explanation:

The area of a rectangle can be determined by the following formula.

A = l ⋅ w

l stands for length or the longer side.

w stands for width or the shorter side.

Now, we can plug the values we are given into the equation.

A = ( x − 2 ) ⋅ ( x + 8 )

The easiest way to multiply is to follow the acronym FOIL , which stands for First Outside Inside Last, and dictates the order in which you multiply these terms.

A = x 2 + 8 x − 2 x −16 = x 2 + 6 x − 16

Now, we can plug in the given value for the area.

39 = x 2 + 6 x − 16

Next, we simplify by moving all terms to one side and factor the equation.

0 = x 2 + 6 x − 55

Finally, we factor the equation. This means we reverse-FOIL, trying to determine the two things that we multiplied together.

0= ( x − 5 ) ⋅ ( x + 11 )

If the equation ultimately equals zero, either ( x − 5 ) or ( x + 11 ) or both equal zero. Therefore, we set each equal to zero to find the value of

x .

x − 5 = 0 x = 5 x + 11 = 0

x = − 11

Since x is a length, we know it cannot be negative. Thus, we can conclude that it equals 5.

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A radio station claims that the amount of advertising per hour of broadcast time has an average of 13 minutes and a standard dev

zimovet [89]

Answer:

$Z = 3.33$

Step-by-step explanation:

Z-score:

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question:

$\mu = 13, \sigma = 1.2$

You listen to the radio station for 1 hour, at a randomly selected time, and carefully observe that the amount of advertising time is equal to 17 minutes. Calculate the z-score for this amount of advertising time.

We have to find Z when X = 17. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{17 - 13}{1.2}$

$Z = 3.33$

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3 years ago

Find the value of x.

blagie [28]

Answer:

Step-by-step explanation:

Ask yo teacher for help bih

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3 years ago

The measure of an angle is 8 times the measure of its complement. tina writes an equation and finds the correct measure of each

pogonyaev

One of the unknown angles (let's called it n) has a complement (meaning their sum adds up to 90 degrees) and the other angle is 8 times the unknown angle (8n)

With all this information, you should have the equation:

n + 8n = 90

To solve, combine like terms to get:

9n = 90

Divide by 9 on both sides to isolate the variable n.

n = 10

Now we plug back in to find our angle measurements. The first angle, n, is 10 degrees. The second angle, 8n, is 8 * 10 which is 80; the second angle is 80 degrees.

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pychu [463]

The correct answer is y=2/3x-1/3

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Shauna makes 24 cupcakes per hour. She has already made 48 cupcakes. Let x represent the amount of time Shauna spends making the

GalinKa [24]

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3 years ago