Factor each completely.

7x^2- 31x-20

5p-p-18 Factor each completely.

7x^2- 31x-20

5p-p-18 @Mathematics

Question

Factor each completely.

7x^2- 31x-20

5p-p-18 Factor each completely.

7x^2- 31x-20

5p-p-18 @Mathematics

saifoo.khan · Answer

$$(x-5) (7 x+4) $$

saifoo.khan · Answer

what's the second thing?

safia21 · Answer

how did you get the first one?

saifoo.khan · Answer

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

saifoo.khan · Answer

so,

7x^2 - 31x - 20

those two terms are, -35 and + 4.

safia21 · Answer

can you do it with the diamond?

saifoo.khan · Answer

umm, no! :o
what's that?

safia21 · Answer

nvrm

anonymous · Answer

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.

anonymous · Answer

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

anonymous · Answer

That post will show you how.

saifoo.khan · Answer

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