Solve for r
r=-R+\frac{\sqrt{2}}{R}
R\neq 0
Solve for R
R=\frac{\sqrt{r^{2}+4\sqrt{2}}-r}{2}
R=\frac{-\sqrt{r^{2}+4\sqrt{2}}-r}{2}
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\left(R+r\right)R=2^{\frac{1}{2}}
Multiply both sides of the equation by 2.
R^{2}+rR=2^{\frac{1}{2}}
Use the distributive property to multiply R+r by R.
rR=2^{\frac{1}{2}}-R^{2}
Subtract R^{2} from both sides.
Rr=-R^{2}+\sqrt{2}
Reorder the terms.
\frac{Rr}{R}=\frac{-R^{2}+\sqrt{2}}{R}
Divide both sides by R.
r=\frac{-R^{2}+\sqrt{2}}{R}
Dividing by R undoes the multiplication by R.
r=-R+\frac{\sqrt{2}}{R}
Divide -R^{2}+\sqrt{2} by R.
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