Solution:
Given system of equations are:
4x + 5y = 7 ------ eqn 1
3x -2y = -12 ------- eqn 2
Multiply eqn 1 by 2
8x + 10y = 14 ------ eqn 3
Multiply eqn 2 by 5
15x - 10y = -60 ------- eqn 4
Add eqn 3 and eqn 4
8x + 10y = 14
15x - 10y = -60
( + ) -------------
23x = -46
Substitute x = -2 in eqn 1
4(-2) + 5y = 7
-8 + 5y = 7
5y = 15
Thus the solution is (x, y) = (-2, 3)