What is the factored form of x^2 + 6x + 8?
I got (x+4) (x+2)

Question

What is the factored form of x^2 + 6x + 8?
I got (x+4) (x+2)

zehanz · Answer

You're right!
Just expand again (FOIL)...

anonymous · Answer

so 5 and 3?

zehanz · Answer

Or use: 
4+2 = 6 (coefficient of x)
4*2 = 8 (constant at the end)

zehanz · Answer

Rule is: the numbers you are looking for have sum 6 and product 8

anonymous · Answer

ah thanks so it is 4 and 2 because 4 + 2 = 6 and 4 x 2 = 8

anonymous · Answer

factoring makes so much sense now thanks

zehanz · Answer

Yes! 
Another one: x²+5x+6 = (x+2)(x+3)

They're not all that easy though, because sometimes there are negative numbers involved, or there seem to be many numbers to choose from...

anonymous · Answer

yeah I see it now :)

zehanz · Answer

E.g. this one: x²-3x-28

Sum = -3 (many possibilities, don't bother with them!)
Prod. = -28...hmm that could be:
(one of them should be negative, because product is negative )

-1, 28 or 1,-28  no: sum goes wrong
-2, 14 or 2, -14 no ....
-4, 7 or 4, -7 ...yes! Sum of 4 and -7 is -3

So: (x-7)(x+4)

Now I will stop ;)