Question

Factor each completely.

7x^2- 31x-20


5p-p-18 Factor each completely.

7x^2- 31x-20


5p-p-18 @Mathematics

Answer 1

\[(x-5) (7 x+4) \]

Answer 2

what's the second thing?

Answer 3

how did you get the first one?

Answer 4

we want two terms to which after multiplication we get 140.
and after addition we get -31.

Answer 5

so,

7x^2 - 31x - 20

those two terms are, -35 and + 4.

Answer 6

can you do it with the diamond?

Answer 7

umm, no! :o
what's that?

Answer 8

nvrm

Answer 9

take the first term 7 and multiply by the last 20 to give 140. Rewrite saying x^2-31x-140. Now factor. Rewrite the two factors containing 7 in front of x.
now factor out each expression and throw away the factor.
Works everytime.

Answer 10

http://mathforum.org/library/drmath/view/56442.html

Answer 11

That post will show you how.

Answer 12

http://www.youtube.com/watch?v=fPjmX2H39dw