SOLUTION: factor by grouping 9a^2-40a-25

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Question 614799: factor by grouping
9a^2-40a-25
Answer by nerdybill(7384) About Me  (Show Source):
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factor by grouping
9a^2-40a-25
rewrite the middle term as:
9a^2 +5a-45a -25
group:
(9a^2+5a)-(45a+25)
a(9a+5)-5(9a+5)
(9a+5)(a-5)