SOLUTION: factor to the nearest tenth x^2+7xy-18y^2

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Question 55371: factor to the nearest tenth
x^2+7xy-18y^2
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B7xy-18y%5E2
(x___y)(x___y)
Two numbers that multiply to get -18 (c), but add together to get 7 (b) are:
9 and -2
9*-2=-18 and 9+(-2)=7
highlight%28%28x%2B9y%29%28x-2y%29%29
Check by foiling:
(x+9y)(x-2y)
x(x)+x(-2y)+9y(x)+9y(-2y)
x%5E2-2xy%2B9xy-18y%5E2
x%5E2%2B7xy-18y%5E2 We're right!!!
Happy Calculating!!!