SOLUTION: How do you factor something like this? 3x^2-16x+5 I have tried many ways to try to factor it, like trying to reduce the 16x into things like 4x^2 and 2x^3, but with no success. Ple

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: How do you factor something like this? 3x^2-16x+5 I have tried many ways to try to factor it, like trying to reduce the 16x into things like 4x^2 and 2x^3, but with no success. Ple      Log On


   



Question 598277: How do you factor something like this? 3x^2-16x+5 I have tried many ways to try to factor it, like trying to reduce the 16x into things like 4x^2 and 2x^3, but with no success. Please, I need help. Thank you!
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


You just take the FOIL process backwards.

Note that the sign on the constant term is positive so the signs in the two factors have to be the same. Since the sign on the first degree term is negative, the two signs must be negative.

The only way to make 5 from two negative factors is -1 times -5. The only way to make 3 is 3 times 1.

So your only two possibilities are:



or



Use FOIL to multiply them out to figure out which one is the correct one, if either (i.e. don't forget the possibility that the original trinomial is prime over the real numbers)

John

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