SOLUTION: 7x+2y=-13 -3x-8y=-23

 7x + 2y = -13,      (1)
-3x - 8y = -23.      (2)

Multiply equation (1) by 3 (both sides). Multiply equation (2) by 7 (both sides). You will get

 21x +  6y =  -39,   (1')
-21x - 56y = -161.   (2')

Add the equations (1') and (2'). You will get

-50y = -200.

Then  y =  = 4.

Now from equation (2) you have 3x = 23 - 8y = 23 - 8*4 = 23 - 32 = -9.

Hence, y =  = -3.

Answer.  x = -3, y = 4.

  7x + 2y = - 13 ------ eq (i)

- 3x - 8y = - 23 ------ eq (ii)

28x + 8y = - 52 ------- Multiplying eq (i) by 4 ------- eq (iii)

25x = - 75 ------ Adding eqs (iii) & (ii)

, or 

7(- 3) + 2y = - 13 ------- Substituting - 3 for x in eq (i)

- 21 + 2y = - 13

2y = - 13 + 21

2y = 8

, or