3x+y=5 , 2x-2y=22 solve the system of equations by the addition method
\(3x+y=5\\ 2x-2y=22\\\\ 3x+y=5\\ \underline{x-y=11}\\ 4x=16\\ x=4\\\\ 4-y=11\\ -y=7\\ y=-7\\\\ \boxed{(x,y)=(4,-7)}\)
3x+y=5
2x-2y=22 ...............2(x-y)=22 ⇒ x-y=11
3x+y=5
x-y=11 (+)
3x+x+y-y=11+5
4x=16 /:4
x=4
x-y=11
4-y=11
-y=7 /*(-1)
y=-7