x = shorts and y = socks
2x + 3y = 33
x + 5y = 27.....multiply by -2
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2x + 3y = 33
-2x - 10y = - 54 (result of multiplying by -2)
------------------add
-7y = - 21
y = -21/-7
y = 3
x + 5y = 27
x + 5(3) = 27
x + 15 = 27
x = 27 - 15
x = 12
so shorts (x) cost $12 and socks (y) cost $ 3 per pack