Factor the polynomial expression.
x^2-6x-7

Question

Factor the polynomial expression. 
x^2-6x-7

whpalmer4 · Answer

Can you think of two numbers which give you  -6 if you add, and -7 if you multiply?

whpalmer4 · Answer

Hint: one is positive, the other is negative

anonymous · Answer

3 and 3?

whpalmer4 · Answer

3 * 3 = -7?!?

whpalmer4 · Answer

@JonyS the idea is to teach HOW to do it, not just supply answers.
See the Code of Conduct link at the bottom of the window

anonymous · Answer

oh should I delete my answer then?

whpalmer4 · Answer

As your penance, please explain how you came up with the factoring...

anonymous · Answer

@whpalmer4 I think he hasn't seen the answer I'll delete it xD

anonymous · Answer

If you are struggling with this you can watch this video: http://www.youtube.com/watch?v=eF6zYNzlZKQ

whpalmer4 · Answer

Nah, leave it up there, I'll just add a bit more about why we do that...

(X+a)(x+b) = x*x +b*x + a*x + a*b = x^2 + (a+b) + ab

Here we have a+b =-6 and a*b=-7

-7*1 =-7
-7+1=-6

So our factoring is (x-7)(x+1)