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SAT Math 5.1 Algebra and Functions 198 Views


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Description:

SAT Math 5.1 Algebra and Functions

Language:
English Language

Transcript

00:02

And here's your shmoop du jour...

00:04

If 3x squared - 6 = 18, what does x squared - 2 equal?

00:10

And here are the possible answers...

00:14

Ok, so the key to this problem is figuring out how 3x squared - 6 = 18 relates

00:21

to x squared - 2.

00:24

And no, he's not her second cousin.

00:27

First, we see that both have an x squared in their equations...

00:31

so let's try solving for that.

00:33

Start with the first equation..

00:35

Add 6 to both sides... so 3x squared = 24.

00:40

Divide both sides by 3, and we have that x squared = 8.

00:45

Now, we can plug x squared = 8 into the second equation:

00:49

x squared - 2 = 8 - 2...which equals 6.

00:54

The answer is A.

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