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Simplifying
510000000 = 4 * 3.14r * r
Multiply 4 * 3.14
510000000 = 12.56r * r
Multiply r * r
510000000 = 12.56r2
Solving
510000000 = 12.56r2
Solving for variable 'r'.
Move all terms containing r to the left, all other terms to the right.
Add '-12.56r2' to each side of the equation.
510000000 + -12.56r2 = 12.56r2 + -12.56r2
Combine like terms: 12.56r2 + -12.56r2 = 0.00
510000000 + -12.56r2 = 0.00
Add '-510000000' to each side of the equation.
510000000 + -510000000 + -12.56r2 = 0.00 + -510000000
Combine like terms: 510000000 + -510000000 = 0
0 + -12.56r2 = 0.00 + -510000000
-12.56r2 = 0.00 + -510000000
Combine like terms: 0.00 + -510000000 = -510000000
-12.56r2 = -510000000
Divide each side by '-12.56'.
r2 = 40605095.54
Simplifying
r2 = 40605095.54
Take the square root of each side:
r = {-6372.212766379, 6372.212766379}
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