In the diagram, the radius of the outer circle is 2x cm and the radius of the inside circle is 6 cm. The area of the shaded region is 160π cm2. What is the value of x? Enter your answer in the box.
x =
let's find the area of the outer circle and the inside circle the inside's circle area A= π x 6²=36π the outer's A' = π x 4x²= 4πx² A'-A=4πx²- 36π=160πcm² equivalent to x²- 9=40, so x²=49 implies x =sqrt(49)=7, x=7
