SOLUTION: -20-3x+3x^2=0 I can't seem to find the right way to factor it!

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Question 152073: -20-3x+3x^2=0
I can't seem to find the right way to factor it!
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Perhaps that is because the trinomial -20-3x%2B3x%5E2=0 is not factorable...in other words, it's prime.
Let's rearrange the trinomial so that it's in standard form:
3x%5E2-3x-20+=+0
The factors, if there were any, would take the form:
%283x%2Bm%29%28x%2Bn%29+=+0 and you need to have m*n = -20 and 3n+m = -3
The factors of -20 are:
-20 = -1*20 or 1*(-20) and 3(-1)+20 = 17, 3(1)+(-20) = -17
-20 = -2*10 or 2*(-10) and 3(-2)+10 = 4, 3(2)+(-10) = -4
-20 = -4*5 or 4*(-5) and 3(-4)+5 = -7, 3(4)+(-5) = 7
So, as you can see, there is no way to get a -3 from combining the factors of -20.
The trinomial is prime!