Ask question

Ask question

All categories

3 years ago

11

An isosceles trapezoid has a perimeter of 40.9 feet. Its shorter base measures 3.5 feet and its longer base measures 4.4 feet. T

he two remaining sides have the same length; what is that length?

2 answers:

anzhelika [568]3 years ago

7 0

Answer:

16.5 feet is the amount of the length

klio [65]3 years ago

6 0

16.5
P= a + b + c + d
40.9 = 3.5 + 4.4
40.9 = 7.9
-7.9 -7.9
---------------
40.9-7.9=33 and since its calculating two equal sides, 33/2 = 16.5

You might be interested in

Violet contributes 12% of her $55,700 annual salary to her 401(k) plan. What is her pretax income?

NikAS [45]

You have that:

- Her contribution from her salary <span>to her 401(k) plan, </span>is: 12%.
- Her annual salary is: $55,700.

Then, to solve this problem and calculate her pretax income, you must following the steps below:

1. You must calculate the amount that Violet contributed to her 401(k) plan. So, you have:

12%/100=0.12

($55,700x0.12)=$6,684

2. Now, you must subtract her annual pay ($55,700) by the amount obtained ($6,684), as below:

Pretax income= $55,700-$6,684
<span> Pretax income=$49,016
</span><span>
What is her pretax income?

The answer is: Her pretax income is </span>$49,016

7 0

4 years ago

Read 2 more answers

An experiment was conducted to observe the effect of an increase in temperature on the potency of an antibiotic. Three 1-ounce p

ludmilkaskok [199]

Answer:

a) $y=-0.317 x +46.02$

b) Figure attached

c) $S^2=\hat \sigma^2=MSE=\frac{190.33}{10}=19.03$

Step-by-step explanation:

We assume that th data is this one:

x: 30, 30, 30, 50, 50, 50, 70,70, 70,90,90,90

y: 38, 43, 29, 32, 26, 33, 19, 27, 23, 14, 19, 21.

a) Find the least-squares line appropriate for this data.

For this case we need to calculate the slope with the following formula:

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

So we can find the sums like this:

$\sum_{i=1}^n x_i = 30+30+30+50+50+50+70+70+70+90+90+90=720$

$\sum_{i=1}^n y_i =38+43+29+32+26+33+19+27+23+14+19+21=324$

$\sum_{i=1}^n x^2_i =30^2+30^2+30^2+50^2+50^2+50^2+70^2+70^2+70^2+90^2+90^2+90^2=49200$

$\sum_{i=1}^n y^2_i =38^2+43^2+29^2+32^2+26^2+33^2+19^2+27^2+23^2+14^2+19^2+21^2=9540$

$\sum_{i=1}^n x_i y_i =30*38+30*43+30*29+50*32+50*26+50*33+70*19+70*27+70*23+90*14+90*19+90*21=17540$

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=49200-\frac{720^2}{12}=6000$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}=17540-\frac{720*324}{12}{12}=-1900$

And the slope would be:

$m=-\frac{1900}{6000}=-0.317$

Nowe we can find the means for x and y like this:

$\bar x= \frac{\sum x_i}{n}=\frac{720}{12}=60$

$\bar y= \frac{\sum y_i}{n}=\frac{324}{12}=27$

And we can find the intercept using this:

$b=\bar y -m \bar x=27-(-0.317*60)=46.02$

So the line would be given by:

$y=-0.317 x +46.02$

b) Plot the points and graph the line as a check on your calculations.

For this case we can use excel and we got the figure attached as the result.

c) Calculate S^2

In oder to calculate S^2 we need to calculate the MSE, or the mean square error. And is given by this formula:

$MSE=\frac{SSE}{df_{E}}$

The degred of freedom for the error are given by:

$df_{E}=n-2=12-2=10$

We can calculate:

$S_{y}=\sum_{i=1}^n y^2_i -\frac{(\sum_{i=1}^n y_i)^2}{n}=9540-\frac{324^2}{12}=792$

And now we can calculate the sum of squares for the regression given by:

$SSR=\frac{S^2_{xy}}{S_{xx}}=\frac{(-1900)^2}{6000}=601.67$

We have that SST= SSR+SSE, and then SSE=SST-SSR= 792-601.67=190.33[/tex]

So then :

$S^2=\hat \sigma^2=MSE=\frac{190.33}{10}=19.03$

5 0

3 years ago

Write 2.71x10-3 as an ordinary number.

Katyanochek1 [597]

Step-by-step explanation:

${2.71 \times 10}^{ - 3}$

This can be rewritten as

$2.71 \times \frac{1}{10^{3} }$

If we will solve this way,

$\frac{2.71}{1000} = 0.00271$

But since the denominator is just in terms of 1, we can just simply get the (-3). Note that we have to take the negative into consideration.

From the original position of the decimal point, move the decimal point 3 times TO THE LEFT. Therefore, from 2.71 we move the decimal point 3 times to the left, 0.00271.

If the exponent has a positive value, move TO THE RIGHT.

For example,

$2.71 \times {10}^{3} = 2.71 \times 1000 \\ = 2710$

Note that the exponent has a positive value. Therefore, we have to move the decimal point 3 times TO THE RIGHT. Producing 2710 as the answer.

5 0

3 years ago

-NEED AN ANSWER FAST-

Zinaida [17]

$25.75 is how much money she saved up each week

5 0

3 years ago

If f(x) = 2x+4, which of the following is the inverse of f(x)?

creativ13 [48]

Answer:

${f}^{ - 1} (x)= \frac{x}{2} - 2$

Step-by-step explanation:

The given function is

$f(x) = 2x + 4$ Let

$y = 2x + 4$

Interchange x and y.

$x = 2y + 4$

Solve for y,

$x - 4 = 2y$

Divide both sides by 2

$y = \frac{x}{2} - 2$

Therefore;

${f}^{ - 1} (x)= \frac{x}{2} - 2$

3 0

3 years ago