Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 155388This question is from textbook
: How do you factor x^2-16x+51This question is from textbook
: How do you factor x^2-16x+51
Answer by Earlsdon(3716) About Me  (Show Source):
You can put this solution on YOUR website!
Remember, not every trinomial is factorable. If not factorable, they are called "prime".
Factor:
x^2-16x+51 Look at the constant term, 51, its factors are 3 and 17.
Now, can you ever get the middle coefficient of -16 by adding or subtracting 3 and 17?
3+17 = 20
-3+(-17) = -20
3-17 = -14
-3-(-17) = 14
The answer is no!
So the trinomial is, therefore, prime!