If the larger radius is r, then we have
πr^2 = π(r-3)^2 + 15π
r^2 = r^2-6r+9 + 15
6r = 24
r = 4
check:
16π = π + 15π
STONE-GROUND FLOUR
The radius of a milestone is 3 meters greater than the radius of another, and their areas differ by 15pi square meters. Find the radius of the larger milestone.
1 answer