First, permit's relate area and Perimeter. The formulation for area is A = &pi r^2 The formulation for perimeter is P = 2 &pi r interior the 2nd formulation, permit's isolate r r = P/(2&pi) substitute this value into the 1st formulation. A = &pi r^2 A = &pi [P/(2&pi)]^2 A = &pi P^2 (a million/[4 &pi^2] ) Which extra simplifies as A = (a million/4) P^2 (&pi / &pi^2 ) And we get a cancellation A = (a million/4) P^2 (a million/&pi) And all of us understand P = 1000, so A = (a million/4)(1000)^2 (a million/&pi) A = ( a million/4 ) (a million/&pi) A = 250000/&pi
This is the quickest method.
Perimeter of circle = 2 * pi * radius = 1000
=> pi* radius = 500
squaring both sides,
pi^2 * radius^2 = 500^2
pi* radius^2 = (500^2)/pi
Now , area of circle = pi * radius^2
= (500^2)/pi (from above)
= 79577.47 m^2