Question

Solve the linear system of equations 4x + 3y = 11 and 2x - 5y = -1

Answer 1

`\left\{\begin{array}{ccc}4x+3y=11\\2x-5y=-1&|\text{multiply both sides by (-2)}\end{array}\right\\\underline{+\left\{\begin{array}{ccc}4x+3y=11\\-4x+10y=2\end{array}\right}\qquad|\text{add both sides of the equtions}\\.\qquad\qquad13y=13\qquad|\text{divide both sides by 13}\\.\qquad\qquad y=1\\\\\text{put the value of y to the first equation}\\\\4x+3(1)=11\\4x+3=11\qquad|\text{subtract 3 from both sides}\\4x=8\qquad|\text{divide both sides by 4}\\x=2\\\\\boxed{Answer:\ x=2\ and\ y=1}`