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Quadratic equations help

The question I have been asked to solve is:
y^2 - 5y = 3y^2 - 6y - 10

I have rearranged it to get -2y^2 + y + 10 = 0 but I don't understand how to factorise this as nothing multiplies to get 10 and adds to get 1
Original post by bulbs
The question I have been asked to solve is:
y^2 - 5y = 3y^2 - 6y - 10

I have rearranged it to get -2y^2 + y + 10 = 0 but I don't understand how to factorise this as nothing multiplies to get 10 and adds to get 1


factors of -20 that add to make 1
(edited 7 years ago)
Original post by bulbs
The question I have been asked to solve is:
y^2 - 5y = 3y^2 - 6y - 10

I have rearranged it to get -2y^2 + y + 10 = 0 but I don't understand how to factorise this as nothing multiplies to get 10 and adds to get 1


Try to get the 2y2-2y^2 coefficient to be positive, by multiplying everything by -1. It should be easier from there.
Reply 3
Original post by ValerieKR
factors of -20 that add to make 1


Thanks.
So -2y^2 - 4y - 5y + 10 = 0
-2y(y+2) + 5(y+2)
(-2y+5)(y+2) = 0
y = 5/2 or y = -2
Original post by bulbs
Thanks.
So -2y^2 - 4y - 5y + 10 = 0
-2y(y+2) + 5(y+2)
(-2y+5)(y+2) = 0
y = 5/2 or y = -2


You've mixed up some signs in your type up but it's right

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