Respuesta :

Answer:

Step-by-step explanation:

18x+7y=-89   equation1

9x-9y=18       equation2

multiplying equation 2 by 2

2(9x-9y=18)    18x-18y=36   equation 3

subtacting equation 1 and 3

18x-18x+7y+18y=-89-36

25y=125

y=5

putting the values of y in equation1

18x+7(5)=-89

18x+35=-89

18x=-89-35

18x=-124

x=-6.8