The way I factor trinomials is by taking the leading and the
last term and multiplying them together. I then take the new number that those
multiplied out to and figure out what two factors of that multiplied number can
equal the middle number. For instance in the following trinomial 10x^2 -11x +
3. First we take and multiply the leading term, 10 by the trailing term, 3.
This gives us 30. We much now factor 30 and find out which two factors of 30
when added together equal the middle term, 11. In the number 30 the factors are
1,2,3,5,6,10,15,30. Right off the bat I can see that 5 and 6 both add up to 11
and multiply to 30. Now our problem is that 5 and 6 do not add up to negative
11 so they must both be negative. So our new polynomial is, 10x^2 -5x -6x +3.
To factor these you must now group and pull out the highest common factor from
each problem. It is very simple! In order to factor this polynomial we have to
pull a 5x out of the first grouping (10x^2-5x) (10x^2-5x) (-6x + 3) 5x(2x-1) -3(2x-1)
(5x-3) (2x-1) x = 1/2 , or 3/5
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