Answer:
![A = 4x^2 + 86x + 450](https://tex.z-dn.net/?f=A%20%3D%204x%5E2%20%2B%2086x%20%2B%20450)
Step-by-step explanation:
Given
![Walkway = x](https://tex.z-dn.net/?f=Walkway%20%3D%20x)
![Length = 18](https://tex.z-dn.net/?f=Length%20%3D%2018)
![Width = 25](https://tex.z-dn.net/?f=Width%20%3D%2025)
Required:
The area of the swimming pool
Assume the walkway will be on the 4 sides of the swimming pool.
The total length (L) of the swimming pool will be:
![L = 18 + x + x](https://tex.z-dn.net/?f=L%20%3D%2018%20%2B%20x%20%2B%20x)
![L = 18 + 2x](https://tex.z-dn.net/?f=L%20%3D%2018%20%2B%202x)
The total width (W) will be:
![W = 25 + x + x](https://tex.z-dn.net/?f=W%20%3D%2025%20%2B%20x%20%2B%20x)
![W = 25 + 2x](https://tex.z-dn.net/?f=W%20%3D%2025%20%2B%202x)
The area (A) is:
![A = L * W](https://tex.z-dn.net/?f=A%20%3D%20L%20%2A%20W)
![A = (18 + 2x) * (25 + 2x)](https://tex.z-dn.net/?f=A%20%3D%20%2818%20%2B%202x%29%20%2A%20%2825%20%2B%202x%29)
Expand bracket
![A = 18 * 25 + 18 * 2x + 25 * 2x + 2x * 2x](https://tex.z-dn.net/?f=A%20%3D%2018%20%2A%2025%20%2B%2018%20%2A%202x%20%2B%2025%20%2A%202x%20%2B%202x%20%2A%202x)
![A = 450 + 36x + 50x + 4x^2](https://tex.z-dn.net/?f=A%20%3D%20450%20%2B%2036x%20%2B%2050x%20%2B%204x%5E2)
![A = 450 + 86x + 4x^2](https://tex.z-dn.net/?f=A%20%3D%20450%20%2B%2086x%20%2B%204x%5E2)
Reorder
![A = 4x^2 + 86x + 450](https://tex.z-dn.net/?f=A%20%3D%204x%5E2%20%2B%2086x%20%2B%20450)
His average is 4.2 seconds. hope it helps
Answer:
12 units
Step-by-step explanation:
x is to 16 as 9 is to x
x/16 = 9/x cross multiply
x^2 = 144
x =12
The answer that you are looking for is PQ, because the radius of a circle is half of the diameter or half of the circle. PQ is the only one that is the whole length of the circle.