5x + y= 9

10x-7y=18

Multiply Eq1 by -2 and add:

-10x - 2y = -18
+10x - 7y = 18
Sum: 0 - 9y = 0
Y = 0

In Eq1, replace Y with 0 and solve for X
-10x - 2*0 = -18
X = 1.8