SOLUTION: Factor completely: x^2 + 12x - 28

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Question 209289: Factor completely:
x^2 + 12x - 28
Found 2 solutions by Earlsdon, rfer:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor completely:
x%5E2%2B12x-28
The factors will have the form:
%28x%2Bm%29%28x%2Bn%29 where m%2An+=+-28 and m%2Bn+=+12
Let's do the -28 factors first:
-28+=+-1%2A18
-28+=+1%2A%28-28%29
-28+=+-2%2A14
-28+=+2%2A%28-14%29
-28+=+-4%2A7
-28+=+4%2A%28-7%29
Now which of the pair of factors, when added, gives you 12?
How about -2 and 14?, so m = -2 and n = 14, thus...
highlight%28x%5E2%2B12x-28+=+%28x-2%29%28x%2B14%29%29

Answer by rfer(16322) About Me  (Show Source):