Question 761397
I'll suggest you to multiply the equation,x+7y=-37 with 2 so that you can get the same coefficient of x as the other equation. then, work can be easier for you!
x2) x+7y=-37               ; 2x-5y=21---Eqn. 2
   2x+14y=-74---Eqn. 1
By method of elimination, Eqn. 1 - Eqn. 2:  
(2x+14y)-(2x-5y)=-74-21
19y=-95
therefore, y=-5.

Substitute y=-5 into any of the equations, then you will get x=-2 as your answer.

Hope I helped!