Question

2x+3y = -33
3x+6y=-57
using elimination

Answer 1

`\left\{\begin{array}{ccc}2x+3y = -33&\text{multiply both sides by 3}\\3x+6y=-57 &\text{multiply both sides by (-2)}\end{array}\right\\\\\underline{\left\{\begin{array}{ccc}6x+9y=-99\\-6x-12y=114 \end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-3y=15\qquad\text{divide both sides by (-3)}\\.\qquad y=-5\\\\\\\text{Put the value of y to the first equation}\\\\2x+3(-5)=-33\\2x-15=-33\qquad\text{add 15 to both sides}\\2x=-18\qquad\text{divide both sides by 2}\\x=-9`

`Answer:\ x=-9\ and\ y=-5\to(-9,\ -5)`