7/x = 5/y
Can be changed to:
5x = 7y
So, x = (7/5)y and
y = (5/7)x
Area=pi times radius^2 so
if area=4pi=pi times r^2
4 times pi=r^2 times pi
divide both sdies by pi
4=r^2
square root
2=radius since legnth cannot be negative
radius=1/2 diamters
2 radius=diameter
2(2)=diameter=4
diameter=4
v + 9 / 3 = 8
v + 9 = 24
v = 24 - 9
v = 15
If you have any questions on how I got to this solution, please ask. :)