Solve {l}{sigma^2+5sigma=10}{pi^2+D^2=10^2}

$$\left. \begin{array} { l } { \sigma ^ { 2 } + 5 \sigma = 10 } \\ { \pi ^ { 2 } + D ^ { 2 } = 10 ^ { 2 } } \end{array} \right.$$

Solve for σ, D

$$\sigma =\frac{-\sqrt{65}-5}{2}\approx -6.531128874\text{, }D=-\sqrt{-\pi ^{2}+100}\approx -9.493702945$$

$$\sigma =\frac{-\sqrt{65}-5}{2}\approx -6.531128874\text{, }D=\sqrt{-\pi ^{2}+100}\approx 9.493702945$$

$$\sigma =\frac{\sqrt{65}-5}{2}\approx 1.531128874\text{, }D=-\sqrt{-\pi ^{2}+100}\approx -9.493702945$$

$$\sigma =\frac{\sqrt{65}-5}{2}\approx 1.531128874\text{, }D=\sqrt{-\pi ^{2}+100}\approx 9.493702945$$