Hello from MrBillDoesMath!
Answer: x = 10, y = 6
Discussion:
Subtract the second equation from the first equation:
3x + y = 36
-5x - y = - 56 (subtraction is same as adding negative)
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(3x - 5x) + ( y-y) = 36 - 56 or
-2x + 0 = -20 or
x = -20/(-2) = + 10
Substituting "x" value in 3x + y = 56 gives
3(10) + y = 36 or
30 + y= 36 or
y = 36 - 30 = 6
Thank you,
MrB