SOLUTION: Please help me solve this problem. factor completely: solve: x^2-3x-40=0

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Question 110336: Please help me solve this problem. factor completely: solve: x^2-3x-40=0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Ask yourself what factors of 40 have a difference of 3
1 x 40 = 40 (40 - 1 = 39)
2 x 20 = 40 (20 - 2 = 18)
4 x 10 = 40 (10 - 4 = 6)
5 x 8 = 40 (8 - 5 = 3) this is the one
x%5E2+-+3x+-+40+=+0
%28x+-+8%29%28x+%2B+5%29+=+0 answer
Note that I make the 8 negative so the 3 comes out negative