Solve for R
R=7
R=-7
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5R^{2}+508.5025=27.45^{2}
Calculate 22.55 to the power of 2 and get 508.5025.
5R^{2}+508.5025=753.5025
Calculate 27.45 to the power of 2 and get 753.5025.
5R^{2}=753.5025-508.5025
Subtract 508.5025 from both sides.
5R^{2}=245
Subtract 508.5025 from 753.5025 to get 245.
R^{2}=\frac{245}{5}
Divide both sides by 5.
R^{2}=49
Divide 245 by 5 to get 49.
R=7 R=-7
Take the square root of both sides of the equation.
5R^{2}+508.5025=27.45^{2}
Calculate 22.55 to the power of 2 and get 508.5025.
5R^{2}+508.5025=753.5025
Calculate 27.45 to the power of 2 and get 753.5025.
5R^{2}+508.5025-753.5025=0
Subtract 753.5025 from both sides.
5R^{2}-245=0
Subtract 753.5025 from 508.5025 to get -245.
R=\frac{0±\sqrt{0^{2}-4\times 5\left(-245\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -245 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
R=\frac{0±\sqrt{-4\times 5\left(-245\right)}}{2\times 5}
Square 0.
R=\frac{0±\sqrt{-20\left(-245\right)}}{2\times 5}
Multiply -4 times 5.
R=\frac{0±\sqrt{4900}}{2\times 5}
Multiply -20 times -245.
R=\frac{0±70}{2\times 5}
Take the square root of 4900.
R=\frac{0±70}{10}
Multiply 2 times 5.
R=7
Now solve the equation R=\frac{0±70}{10} when ± is plus. Divide 70 by 10.
R=-7
Now solve the equation R=\frac{0±70}{10} when ± is minus. Divide -70 by 10.
R=7 R=-7
The equation is now solved.
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