Given: concentric circles with radio of lengths r and r with r> r. prove: a ʳᶦⁿᵍ= π(bc)²

See below.

Step-by-step explanation:

Area of outer circle = π R^2

and area of the inner circle  = π r^2 so the area of the ring

= π (R^2 - r^2)   (Equation (1) ).

Consider the triangle OBC. We have, by Pythagoras,  R^2 = r^2 + BC^2.

So BC^2 = R^2 - r^2.

Substituting for R^2 - r^2 in  equation (1):

Area of the ring = π BC^2 as required.

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step-by-step explanation: