3x + 2y = 14 --> equation (1)
2x + 7y = 15 ---> equation (2)
multiply equation (1) by 7
and multiply equation (2) by -2
21x + 14y = 98 equation (1)
-4x -14y = -30 equation (2)
21x -4x = 98 -30
17x = 68
x = 4
not by substitution in any equation by x = 4
3x + 2y = 14
3(4) + 2y = 14
12 + 2y = 14
2y = 14-12
2y = 2
y = 1
so x = 4
and y = 1
