The solution is (x,y) = (2,-3).
Explanation:
4x+9y = -19 ---------(1)
-4x-7y = 13 -----------(2)
2y = -6
The value of y is y= -6/2 = -3.
∴ y= -3, subsitute in any of the above equation.
Substituting y= -3 in eq (1),
⇒ 4x + 9(-3) = -19
⇒ 4x = -19 + 27
⇒ 4x = 8
x = 2