SOLUTION: I'm trying to factor -x^2+6x-8 please.

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Question 271325: I'm trying to factor -x^2+6x-8 please.
Found 3 solutions by unlockmath, LarissaRichardson, solver91311:
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
Let's pull out the negative like this:
-x^2+6x-8 rewritten as:
-1(x^2-6x+8) Now we can factor it like this:
-1(x-4)(x-2)
There we go. Make sense?
Check out a book that might help.
www.math-unlock.com

Answer by LarissaRichardson(34) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply by -1 to get:
x^2-6x+8
Now Reverse FOIL
What times what will give you x^2?
Answer: (x___)(x___)
F:x^2
O
I
L
Next, what times what will give you 8 but added together will give you -6?
Answer: -2 times -4 will give you 8 and -2 + -4 will give you -6!
(x-2)(x-4)
F:x^2
O:-4x
I:-2x
L:8
Which gives you: x^2-4x-2x+8---add like terms----> x^2-6x+8 (look familiar?)
Now set them both equal to zero if asked to:
x-2=0 which is x=2
x-4=0 which is x=4

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Factor out -1 to start:





Now note that -2 times -4 is +8 and -2 plus -4 is -6, so:




John