Solve the simultaneous equations: 2x + y = 18, x - y = 6
Label each equation:2x + y = 18 (1)x - y = 6 (2)Since the y's have the same coefficient (ignoring the signs) you want to cancel the y's to leave just an equation with x.add (1) to (2):3x = 24Then rearrange for x as normal:x = 8 (3)Sub (3) into either (1) or (2):8 - y = 6Rearrange for y as normal:y = 2
MH
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