SOLUTION: Factor each trinomial: 6). 18x^2-27x-5 8). 18y^2+ 9y -5

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Question 16268: Factor each trinomial:
6). 18x^2-27x-5
8). 18y^2+ 9y -5
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
What are the factors of 18x^2?
(x)(18x) or (-x)(-18x) = 18x^2
(2x)(9x) or (-2x)(-9x) = 18x^2
(3x)(6x) or (-3x)(-6x) = 18x^2
What are the factors of -5?
(1)(-5)
(-1)(5)
For problem 6) you need the right combination that will make -27x for the middle term.
Try (3x - 5)(6x + 1) and check using FOIL:
%283x+-+5%29%286x+%2B+1%29+=+18x%5E2+%2B+3x+-+30x+-+5 = 18x%5E2+-+27x+-+5
For problem 8) you need the right combination that will make +9x (or +9y) for the middle term. Use y instead of x from the above factors.
Try (3y - 1)(6y + 5) and check using FOIL.
%283y+-+1%29%286y+%2B+5%29+=+18y%5E2+%2B+15y+-+6y+-+5 = 18y%5E2+%2B+9y+-+5