SOLUTION: How do you factor the following expression using the FOIL Method? 13x^2-17x-6 -I have already layed out many possible solutions with finding 13x^2 and 6 but cannot for the li

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Question 879077: How do you factor the following expression using the FOIL Method?
13x^2-17x-6
-I have already layed out many possible solutions with finding 13x^2 and 6 but cannot for the life of me find 17x
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
That has so few possibilities to check.
13 can only form with factors 1 and 13.
-6 can only form with factors -1 & 6; 1 & -6; -2 & 3; or 2 & -3. Which combinations work?
Focus on which of these will give -17x:
(13x-1)(x+6)?
(13x-6)(x+1)?
(13x+1)(x-6)?
(13x+6)(x-1)?
(13x-2)(x+3)?
(13x+2)(x-3)?
(13x-3)(x+2)?
(13x+3)(x-2)?

Are you sure that 13x^2-17x-6 is a perfect square?



SLIGHTLY MORE ADVANCED---------

Discriminant, %28-17%29%5E2-4%2A13%2A%28-6%29
289%2B52%2A6
289%2B312
Discriminant is 601.
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sqrt%28601%29=stillIrrational
You in fact do NOT have a perfect square trinomial, so your trinomial
is not factorable.