x + 3y = 13 ...(1)
-3x + 2y = 27 ...(2)
Rearrange (1) as x = 13 - 3y ...(3)
Put this into equation (2)
-3*(13 - 3y) + 2y = 27
-39 + 9y + 2y = 27
-39 + 11y = 27
Add 39 to both sides
11y = 66
Divide both sides by 11
y = 6
Put this into equation (3)
x = 13 - 3*6
x = -5
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