9514 1404 393
Answer:
pool radius is 8+4√5 ≈ 16.94 meters
Step-by-step explanation:
Let r represent the radius of the pool. Then r+2 is the radius to the outside of the walkway. The ratio of areas is given as 4/5, so we have ...
πr²/(π(r+2)²) = 4/5
5r² = 4(r² +4r +4) . . . . cross-multiply
r² -16r -16 = 0 . . . . . . . subtract the right-side expression from both sides
__
r² -16r +64 = 80 . . . . . add 80 to complete the square
(r -8)² = 80
r -8 = √80 = 4√5 . . . . square root; use only the positive root
r = 8 +4√5 ≈ 16.94 . . . meters
The radius of the pool is 8+4√5 ≈ 16.94 meters.
_____
The area of a circle of radius r is given by the formula ...
A = πr²
Answer:
a^3 + a^2
Step-by-step explanation:
Distribute the term left of each set of parentheses, then combine like terms.
-a²(3a - 5) + 4a(a² - a) =
= -3a^3 + 5a^2 + 4a^3 - 4a^2
= a^3 + a^2
There two zero’s hopefully
Answer:
The number is 1/4
___________________
Step-by-step explanation:
Look at the photo below for the details.
:)