ShmoopTube

00:03

Your doctor told us you couldn’t handle too much excitement, so here’s an unshmoopy question for you…

00:08

Simplify the following expression:

00:11

x squared plus 4x minus 32 over x squared minus 2x minus 8.

00:16

And here are the potential answers…

00:22

So… what is this question asking?

00:24

Can we simplify something that’s… um… not so simple?

00:28

Looking at the form of these polynomials, the word ‘quadratic’ should be screaming at us.

00:34

And we have to factor the crap out of this one.

00:36

So let’s do it. From the top… literally… we know that 8 times 4 is 32

00:42

and one has to be negative because the 32 is negative…

00:45

...but the 4 in the middle is positive… so it has to be the quantity (x – 4) times (x + 8).

00:56

On the bottom, we have 2 and 4 as natural factors of 8, and 8 is negative…

01:03

and so is the 2. So we have:

01:05

(x -4) times (x+2)

01:15

We can then just cross out the two (x – 4)’s… and we are left with x plus 8 over x plus 2.

01:24

The answer is A.

01:25

As in, “Eh.."

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