SOLUTION: x^2 – 8x + 15 factor completely idk how to do it any help????????

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Question 363076: x^2 – 8x + 15
factor completely idk how to do it
any help????????
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Look for two numbers that add up to (-8) and whose product is (15).
If you look at the factors of 15 (15,1) (3,5).
If you add (-3) and (-5) you get (-8).
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highlight%28x%5E2-8x%2B15=%28x-3%29%28x-5%29%29

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

x^2 – 8x + 15 

factor completely

*Note: factoring is expressing the above as (x -?)(x - ?) where ?s are numbers

whose product is 15.

x^2 – 8x + 15 

(x - 5)(x - 3) Important!!! the 5 and 3 work because -5x + -3x = -8x (the middle term)



checking our answer:

(x - 5)(x - 3) = x(x-3) -5(x-3) = x^2 - 3x -5x +15 = x^2-8x + 15