Problema Solution
The combined area of two circles is 245π square centimeters. The length of a radius of one circle is twice the length of a radius of the other circle. Find the length of the radius of each circle.
Answer provided by our tutors
let radius of two circles be r1 and r2
we have r1=2r2 and
pi*(r1^2 + r2^2) = 245 pi
==> 5r2^2 = 245
==> r2^2 = 49
==> r2 = 7 cm
hence, r1 = 14 cm