SOLUTION: Hi, How do I solve by factoring: x^2 - 2x - 15 =0 txs.

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Question 64586This question is from textbook college algebra
: Hi,
How do I solve by factoring:
x^2 - 2x - 15 =0
txs.
 This question is from textbook college algebra

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by factoring:
x%5E2-2x-15+=+0
To factor this, the factors will have the form:
(x+m)(x+n) where: m+n = -2 and m*n = -15
Try: m = 3 and n = -5
m+n = 3+(-5) = -2
m*n = 3(-5) = -15
These will work, so:
x%5E2-2x-15+=+%28x%2B3%29%28x-5%29
%28x%2B3%29%28x-5%29+=+0 Apply the zero product principle.
x%2B3+=+0 and/or x-5+=+0
If x%2B3+=+0 then x+=+-3
If x-5+=+0 then x+=+5
The solutions: x = -3 or x = 5