SOLUTION: axb=-144 a+b=-7 solve using algebra?

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Question 703345: axb=-144
a+b=-7
solve using algebra?

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
axb=-144
a+b=-7
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Use * (Shift 8) for multiply
a*b=-144
a+b=-7
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Find 2 factors of 144 that differ by 7, one +, one minus.
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Factors:
1*144
2*72
3*48
4*36
6*24
8*18
9*16 difference = 7
--> -16 and 9
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Using algebra:
a*b=-144
a+b=-7 --> b = -a-7
Sub for b in the 1st eqn
a*(-a-7) = -144
-a%5E2+-+7a+=+-144
a%5E2+%2B+7a+-+144+=+0
Now find 2 factors of -144 that differ by 7, same as above.
(a + 16)*(a - 9) = 0
a = 9, b = -16 or vice versa
same answer