Question

3x-4y=18 x 3y=-7 how do i solve this

Answer 1

3 times (2) gives 3x +9y = -21 (3) 
(3) - (1) gives 13y = -39 
y = -3 
Sub. y=-3 into (2) 
x + -9 = -7 
x = 2 

Answer = (2,-3)