divide:

(x^2-6x-7)/(3x^2-147) divided by (x^2+8x+7)/(x^2+14x+49)

here's what i have so far--
(x^2-6x-7)/(3x^2-147) * (x^2+14x+49)/(x^2+8x+7)

i factored it out--

(x+1)(x-7)/3x^2-147 * (x+7)(x+7)/(x+1)(x+7)

what im getting stuck on is the 3x^2-147. I know i have to get it to 3(x^2-27), but i cant factor it further after that, right? and my online homework program wont accept it as just 3(x^2-27). I tried to find factors of 27 but it's only 1, 3, 9 and 27. Am I missing something completely obvious? I'm at a loss here.

Question

divide:

(x^2-6x-7)/(3x^2-147) divided  by (x^2+8x+7)/(x^2+14x+49)

here's what i have so far--
(x^2-6x-7)/(3x^2-147)  * (x^2+14x+49)/(x^2+8x+7)

i factored it out--

(x+1)(x-7)/3x^2-147 * (x+7)(x+7)/(x+1)(x+7)

what im getting stuck on is the 3x^2-147. I know i have to get it to 3(x^2-27), but i cant factor it further after that, right? and my online homework program wont accept it as just 3(x^2-27). I tried to find factors of 27 but it's only 1, 3, 9 and 27. Am I missing something completely obvious? I'm at a loss here.

anonymous · Answer

you sure it is a square and not a cube?

anonymous · Answer

$$x^3-27$$ factors because it is the difference of two cubes 
just asking, maybe it is not

anonymous · Answer

it's definitely a square

anonymous · Answer

yes, so it is

anonymous · Answer

hmm apparently the correct answer is $\frac{1}{3}$ so lets see how we can get that ...

anonymous · Answer

lol

anonymous · Answer

oh gosh okay

anonymous · Answer

it is not $$3x^2-147=3(x^2-27)$$ it is $$3x^2-147=3(x^2-49)$$

anonymous · Answer

arithmetic will screw you up every time
you good from there?

anonymous · Answer

.. yes omg,, of course it was a simple mistake wow
thank you for your help