Question

Find the approximate solution of this system of equations x+5y=10
3x+y=1

Answer 1

x = -0.357, y = 2.071

Explanation:

`\left\{\begin{array}{ccc}x+5y=10\\3x+y=1&\text{multiply both sides by (-5)}\end{array}\right\\\underline{+\left\{\begin{array}{ccc}x+5y=10\\-15x-5y=-5\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-14x=5\qquad\text{divide both sides by (-14)}\\.\qquad x=-(5)/(14)\to x\approx-0.357\\\\\text{Put it to the equation}\ 3x+y=1:\\\\3(-0.357)+y=1\\-1.071+y=1\qquad\text{add 1.071 to both sides}\\y=2.071`