SOLUTION: Please help me solve this trinomial by factoring:{{{4x^2+5x-9}}}

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Question 33808: Please help me solve this trinomial by factoring:4x%5E2%2B5x-9
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
4X^2+5X-9
COEFFICIENT OF X^2=4
CONSTANT TERM =-9
PRODUCT OF THE 2 NUMBERS=-36
FIND 2 FACTORS FOR THIS WHOSE SUM IS COEFFICIENT OF X TERM =5...WE FIND THAT 9*-4=-36 AND 9-4=5...SO WE SPLIT X TERM IN THIS WAY
4X^2+9X-4X-9...TAKE COMMON FACTORS...
=X(4X+9)-1(4X+9)=(X-1)(4X+9)..IF THIS IS =0 THEN X=1 OR X=-9/4
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