-x-12y=11,7x+4y=3 would be better if written as
-x-12y=11
7x+4y=3 Trick: Mult the first equation by 7, so you'll have -7x there and +7x in the 2nd equation. Thus, you can eliminate x
and focus on finding y.
-7x - 84y = 77
7x + 4y = 3
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-80y = 80, and so y = -1. Use either of the given equations and y= -1 to determine the value of x.
x = ?
y = -1
Solution has the form (x, -1).
