Question 722870: Say you have a question asking you to factor 4x^2+19x+12=0 I know that the first step would be to separate 19x into something like 10x and 9x. Next you put it back in and get 4x^2+10x+9x+12=0. From there i got x(4x+5)but im not sure what to do what to finish this.
Found 2 solutions by solver91311, josgarithmetic:
Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!
You forgot a very important pair of steps.
Step 1: Multiply the lead coefficient by the constant term.
Step 2: Find a pair of factors of the result whose sum is the first degree term coefficient, and then divide the first degree term there.
4 times 12 is 48. You want to find a + b = 19 where ab = 48.
John
Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
Answer by josgarithmetic(39620)  (Show Source):
You can put this solution on YOUR website! Just looking at the polynomial, a person would usually not know, but these arrangements should be examined:
(4x______)(x_______),
and
(2x_____)(2x________).
Look for a pairs of numbers which give product of 12, but when the resulting "I" and "O" products are summed, give 19x. I am specifically referring to the F.O.I.L. multiplication process for two binomials.
F.O.I.L. stands for "first, outer, inner, last."
As an example, (a+b)(c+d), first is ac, outer is ad, inner is bc, last is bd.
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