SOLUTION: Factor completly 2y^2 -6y -56

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Question 997671: Factor completly
2y^2 -6y -56
Found 3 solutions by rothauserc, MathLover1, MathTherapy:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
2y^2 -6y -56 =
2 * (y + 4) * (y - 7)



Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

2y%5E2+-6y+-56
2%28y%5E2+-3y%29+-56
2%28y%5E2+-3y%2B_%29-2%2A_+-56....recall %28a-b%29%5E2=a%5E2-2ab%2Bb%5E2;you have a=1 and 2ab=3, find b
2ab=3=>2%2A1%2Ab=3=>2b=3=>b=3%2F2
square it and plug it in 2%28y%5E2+-3y%2B_%29-2%2A_+-56
2%28y%5E2+-3y%2B%283%2F2%29%5E2%29-2%2A%283%2F2%29%5E2+-56
2%28y+-3%2F2%29%5E2-cross%282%29%2A%289%2Fcross%284%292%29+-56
2%28y+-3%2F2%29%5E2-9%2F2+-56
2%28y+-3%2F2%29%5E2-9%2F2+-112%2F2
2%28y+-3%2F2%29%5E2-121%2F2



Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Factor completly
2y^2 -6y -56
2y%5E2+-+6y+-+56 

2%28y%5E2+-+3y+-+28%29

highlight_green%282%28y+-+7%29%28y+%2B+4%29%29