SOLUTION: A circle is tangent to both the axes .If the distance from the origin to center of the circle is "r" then what is the area of the circle?

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Question 1041755: A circle is tangent to both the axes .If the distance from the origin to center of the circle is "r" then what is the area of the circle?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The circle could be in any one of the four quadrants. Assume for ease, quadrant 1. You are expecting to use r for the distance from Origin to Center. You have then x and y values so that x%5E2%2By%5E2=r%5E2 and that x=y. Call these two equal values, c. You have c%5E2%2Bc%5E2=r%5E2 and this is using c as the RADIUS OF THE CIRCLE, maybe not the best variable choice - but you already described r to be something other than any radius.

2c%5E2=r%5E2
c%5E2=r%5E2%2F2

Area of circle is pi multiplied by radius squared, or
area is pi%2Ac%5E2
%28pi%2F2%29r%5E2-------and again, here r is NOT the radius of the circle.