Question

-5x+7y=11 -5x+3y=19 Elimination

Answer 1

$\left\{\begin{array}{ccc}-5x+7y=11&\text{change the signs}\\-5x+3y=19\end{array}\right\\\underline{+\left\{\begin{array}{ccc}5x-7y=-11\\-5x+3y=19\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad\qquad-4y=8\qquad\text{divide both sides by (-4)}\\.\qquad\qquad \boxed{y=-2}\\\\\text{Upt the value of y to the second equation:}\\\\-5x+3(-2)=19\\-5x-6=19\qquad\text{add 6 to both sides}\\-5x=25\qquad\text{divide both sides by (-5)}\\\boxed{x=-5}\\\\Answer:\ \boxed{x=-5\ and\ y=-2\to(-5,\ -2)}$