Solve {l}{Sigmay=21}{Sigmax^2=76}{Sigmay^2=91}{a=Sigmax}{text{Solvefor}btext{where}}{b=a}

$$\left. \begin{array} { l } { \Sigma y = 21 }\\ { \Sigma x ^ {2} = 76 }\\ { \Sigma y ^ {2} = 91 }\\ { a = \Sigma x }\\ { \text{Solve for } b \text{ where} } \\ { b = a } \end{array} \right.$$

Solve for Σ, y, x, a, b

$$x=-\frac{2\sqrt{1729}}{21}\approx -3.960118645\text{, }y=\frac{13}{3}\approx 4.333333333\text{, }Σ=\frac{63}{13}\approx 4.846153846\text{, }a=-\frac{6\sqrt{1729}}{13}\approx -19.191344203\text{, }b=-\frac{6\sqrt{1729}}{13}\approx -19.191344203$$

$$x=\frac{2\sqrt{1729}}{21}\approx 3.960118645\text{, }y=\frac{13}{3}\approx 4.333333333\text{, }Σ=\frac{63}{13}\approx 4.846153846\text{, }a=\frac{6\sqrt{1729}}{13}\approx 19.191344203\text{, }b=\frac{6\sqrt{1729}}{13}\approx 19.191344203$$