SOLUTION: how do u factorise X squared + 9X + 20

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Question 20188: how do u factorise X squared + 9X + 20
Found 2 solutions by elima, Earlsdon:
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B9x%2B20
You need to find 2 factors of 20; that when you add them together they equal 9.
4,5
(x+5)(x+4)
Hope you understand!
=)

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Try this:
Look for two integers whose product is +20 and whose sum is +9.
20 = (4)(5) and 4+5 = 9 So these become the constants in the two factors.
x%5E2+%2B+9x+%2B+20+=+%28x+%2B+4%29%28x+%2B+5%29