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3 years ago

Write an equation from the information given: A rectangle is twice as long as it is wide. The perimeter of the rectangle is 18.

Mathematics

1 answer:

Agata [3.3K]3 years ago

3 0

Let width = x, Therefore the length must equal 2x

Therefore insert these values on the sides of a rectangle.

Add: 2x + 2x + x + x = 18

Therefore 6x = 18

x = 3

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Find x and y and i just need the answer, no need to show work.

vichka [17]

Answer:

x= 20

y = 60

Step-by-step explanation:

y = 3x

6(3x) = 360

3x = 360/6

3x = 60

x = 20

y = 3*20

y = 60

7 0

1 year ago

A standard piece of paper is 0.05 mm thick. Let's imagine taking a piece of paper and folding the paper in half multiple times.

tatyana61 [14]

Answer:

(a) $g(n)=0.05\cdot 2^n$

(b) $g^{-1}(n)=\log_{2}20g(n)$

Step-by-step explanation:

Part A

The paper's thickness = 0.05mm

When the paper is folded, its width doubles (increases by 100%).

The thickness of the paper grows exponentially and can be modeled by the function:

$g(n)=0.05(1+100\%)^n\\\\g(n)=0.05\cdot 2^n$

Part B

$g(n)=0.05\cdot 2^n\\2^n=\dfrac{g(n)}{0.05}\\ 2^n=20g(n)\\$Changing to logarithm form, we have:\\\log_{2}20g(n)=n\\$Therefore:\\g^{-1}(n)=\log_{2}20g(n)$

Part C

If the thickness of the paper, g(n)=384,472,300,000 mm

Then:

$g^{-1}(n)=\log_{2}20g(n)\\g^{-1}(n)=\log_{2}20\times 384,472,300,000\\=\dfrac{\log 20\times 384,472,300,000}{\log 2} \\g^{-1}(n)=42.8 \approx 43\\n=43$

You must fold the paper 43 times to make the folded paper have a thickness that is the same as the distance from the earth to the moon.

3 0

2 years ago

Multiply.Express your answer in standard form.(3 points)(x² -4x + 3)(-3x²+ 7x –1)

bija089 [108]

Answer:

-3x^{4} + 19x^{3} - 38x^{2} + 25x - 3

Step-by-step explanation:

1) distribute x² into (-3x² + 7x - 1) to get: -3x^{4} + 7x³ - x²

2) distribute -4x into (-3x² + 7x - 1) to get: 12x³ - 28x + 4x

3) distribute 3 into (-3x² + 7x - 1) to get: -9x² + 21x - 3

4) combine all the answers together into one equation:

-3x^{4} + 7x³ - x² + 12x³ - 28x² + 4x - 9x² + 21x - 3

5) combine like terms:

7x³ + 12x³ = 19x³

-x² + -28x² + -9x² = -38x²

4x + 21x = 25x

6) combine answers together into one equation:

-3x^{4} + 19x³ - 38x² + 25x - 3

3 0

3 years ago

Write the value of the underlined digit 7,270

RSB [31]

I am sorry but I do not see the underlined digit, but I will put it this way. 7 in the thousands place is worth 7000, 2 in the hundreds place is worth 200, 7 in the tens place is worth 70, and 0 in the ones place is worth 0.

Hope this helped!

Nate

3 0

3 years ago

Isabella averages 152 points per bowling game with a standard deviation of 14.5 points. Suppose Isabella's points per bowling ga

Serga [27]

Answer:

The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

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:

$\mu = 152, \sigma = 14.5$

The z-score when x=187 is ...

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

$Z = \frac{187 - 152}{14.5}$

$Z = 2.41$

The z-score when x=187 is 2.41. The mean is 187. This z-score tells you that x = 187 is 2.41 standard deviations above the mean.

3 0

2 years ago