Explanation:
elimination means that we multiply one or both equations by certain numbers, so that the sum of terms of the same variable across both equations is 0.
then the sum of both equations is one equation in one variable.
with the solution of that we go into any of the original equations to solve for the second variable.
I suggest in our case to multiply the first equation by -4. and then x add both equations.
-4x - 16y = -88
4x + y = 13
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0 - 15y = -75
y = -75/-15 = 5
with this y = 5 we go e.g. into the second original equation.
4x + 5 = 13
4x = 8
x = 8/4 = 2