CAHSEE Math 1.5 Algebra I

CAHSEE Math 1.5 Algebra I. Find the solution to the absolute value inequality.

Algebra ISolving absolute values
CAHSEE MathAlgebra I
FunctionsAbsolute Value Functions
LanguageEnglish Language
MathAlgebra

Transcript

00:27

We have to put numbers on either side of our variable… so we have a range for x.

00:33

We really have 2 equations we’re solving here as with any absolute value problem…

00:38

and we start with the rosy, positive one.

00:41

First assume that the absolute value things don’t exist… and it’s just the quantity

00:44

x minus 3 is less than 7.

00:47

So we add 3 to both sides to get x is less than 10. We know 10 is on the end… and we

00:52

can cross out A or B as potential answers.

00:55

But now let’s think about how we solve for the LESS THAN part of the equation.

01:00

We need to flip the little “greater than” thingy here – how do we do that?

01:04

We multiply by a negative number – in this case… negative 1.

01:07

So think about it as negative 1 times the quantity x minus 3… all now GREATER than 7.

01:13

We get negative x plus 3 is greater than 7…

01:17

Subtract 3 from both sides to get negative x is greater than 4…

01:21

…then divide both sides by negative one to get x is greater than negative 4…

01:26

So our answer is C.

01:27

As in, “Claustrophobia.”