SOLUTION: factor completely: (((3x^2-2x-8)))

Algebra ->  Algebra  -> Expressions-with-variables -> SOLUTION: factor completely: (((3x^2-2x-8)))      Log On

Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!
Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

   

Question 111046This question is from textbook Intermediate Algebra
: factor completely:
(((3x^2-2x-8)))This question is from textbook Intermediate Algebra

Found 2 solutions by scott8148, oberobic:
Answer by scott8148(5895) About Me  (Show Source):
Answer by oberobic(2302) About Me  (Show Source):
You can put this solution on YOUR website!
The general form of the equation is:
ax%5E2%2Bbx%2Bc
To factor you have to look at the relation of a, b, and c.
In this case, we have:
a=3
b=-2
c=-8
8 can be factored only into 2*4.
Since c is negative we have a case where one factor has a + and the other has -.
3 is a prime number, so it cannot be factored.
So, the only possible solutions are:
%283x+%2B+2%29%28x+-+4%29=+3x%5E2-12x%2B2x-8+=+3x%5E2-10x-8 (not what we want)
%283x+-+2%29%28x+%2B+4%29=+3x%5E2%2B12x-2x-8+=+3x%5E2%2B10x-8 (not what we want)
%283x+-+4%29%28x+%2B+2%29=+3x%5E2%2B6x-4x-8+=+3x%5E2%2B2x-8 (not what we want)
%283x+%2B+4%29%28x+-+2%29=+3x%5E2-6x%2B4x-8+=+3x%5E2-2x-8 (what we want!!)