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borishaifa [10]

3 years ago

7

I need help in this one please?

1 answer:

bazaltina [42]3 years ago

7 0

The answer is c 525.5 square feet

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What is the measure of

Anestetic [448]

It’s either 100 or 130

8 0

3 years ago

A norman window is constructed by adjoining a semicircle to the top of an ordinary rectangular. Find the dimensions of a norman

Yanka [14]

Answer:

$W\approx 8.72$ and $L\approx 15.57$ .

Step-by-step explanation:

Please find the attachment.

We have been given that a norman window is constructed by adjoining a semicircle to the top of an ordinary rectangular. The total perimeter is 38 feet.

The perimeter of the window will be equal to three sides of rectangle plus half the perimeter of circle. We can represent our given information in an equation as:

$2L+W+\frac{1}{2}(2\pi r)=38$

We can see that diameter of semicircle is W. We know that diameter is twice the radius, so we will get:

$2L+W+\frac{1}{2}(2r\pi)=38$

$2L+W+\frac{\pi}{2}W=38$

Let us find area of window equation as:

$\text{Area}=W\cdot L+\frac{1}{2}(\pi r^2)$

$\text{Area}=W\cdot L+\frac{1}{2}(\pi (\frac{W}{2})^2)$

$\text{Area}=W\cdot L+\frac{\pi}{2}(\frac{W}{2})^2)$

$\text{Area}=W\cdot L+\frac{\pi}{2}(\frac{W^2}{4})$

$\text{Area}=W\cdot L+\frac{\pi}{8}W^2$

Now, we will solve for L is terms W from perimeter equation as:

$L=38-(W+\frac{\pi }{2}W)$

Substitute this value in area equation:

$A=W\cdot (38-W-\frac{\pi }{2}W)+\frac{\pi}{8}W^2$

Since we need the area of window to maximize, so we need to optimize area equation.

$A=W\cdot (38-W-\frac{\pi }{2}W)+\frac{\pi}{8}W^2$

$A=38W-W^2-\frac{\pi }{2}W^2+\frac{\pi}{8}W^2$

Let us find derivative of area equation as:

$A'=38-2W-\frac{2\pi }{2}W+\frac{2\pi}{8}W$

$A'=38-2W-\pi W+\frac{\pi}{4}W$

$A'=38-2W-\frac{4\pi W}{4}+\frac{\pi}{4}W$

$A'=38-2W-\frac{3\pi W}{4}$

To find maxima, we will equate first derivative equal to 0 as:

$38-2W-\frac{3\pi W}{4}=0$

$-2W-\frac{3\pi W}{4}=-38$

$\frac{-8W-3\pi W}{4}=-38$

$\frac{-8W-3\pi W}{4}*4=-38*4$

$-8W-3\pi W=-152$

$8W+3\pi W=152$

$W(8+3\pi)=152$

$W=\frac{152}{8+3\pi}$

$W=8.723210$

$W\approx 8.72$

Upon substituting $W=8.723210$ in equation $L=38-(W+\frac{\pi }{2}W)$ , we will get:

$L=38-(8.723210+\frac{\pi }{2}8.723210)$

$L=38-(8.723210+\frac{8.723210\pi }{2})$

$L=38-(8.723210+\frac{27.40477245}{2})$

$L=38-(8.723210+13.70238622)$

$L=38-(22.42559622)$

$L=15.57440378$

$L\approx 15.57$

Therefore, the dimensions of the window that will maximize the area would be $W\approx 8.72$ and $L\approx 15.57$ .

8 0

3 years ago

If Cody is draining his hot tub which holds 1,400 gallons of water at a rate of 27 gallons a minute, what impact will it have on

inessss [21]

Facts:

- tub has 1400 gallons

- draining at 27 gallons/minute

How much water will be left after 18 minutes?

We know that after 1 minute, there will be 27 gallons less.

So after 18 minutes, there must be 18 times less water.

27 x 18 = 486

This is how much water was lost in 18 min

So to find out how much he had left after <u>486 is subtracted.</u>

Therefore, the answer is A) -486 gallons

4 0

3 years ago

If g(x) = 1 - ¾ x <br> find: -5g(4) - 1

cricket20 [7]

Answer:

<u>-</u><u>5</u><u>g</u><u>(</u><u>4</u><u>)</u><u> </u><u>-</u><u> </u><u>1</u><u> </u><u>is</u><u> </u><u>9</u>

Step-by-step explanation:

$g(x) = 1 - \frac{3}{4} x$

when x is 4:

$g(4) = 1 - \frac{3}{4} \times 4 \\ = 1 - 3 \\ = - 2$

therefore:

$- 5g(4) - 1 = - 5( - 2) - 1 \\ = 10 - 1 \\ = 9$

5 0

3 years ago

Read 2 more answers

What is the value of the expression 0.52?

polet [3.4K]

Answer:

0.25

Step-by-step explanation:

lets say you have half a cake

multiplying a decimal is the same as multiplying its counterpart

basically, you divide half a cake in half

0.25 of a cake, or 1/4

uwu

6 0

3 years ago

Read 2 more answers