Question 82296
2X+2Y-1
X-Y      MULTIPLY EACH TERM IN THE SECOND EQ. BY EACH TERM IN THE FIRST EQ.
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2X^2+2XY-X-2XY-2Y^2+Y NOW COMBINE LIKE TERMS.
2X^2-X+Y-2Y^2 (NOTE: THE +2XY-2XY TERMS CANCEL OUT)