# Algebra help! Interval notations

1. Jan 22, 2012

### Johnyi

1. The problem statement, all variables and given/known data

State the meaning of {x:-4<x≤10} in words. Express the set {x:-4<x≤10} using interval notation and draw it on a number line.

2. Relevant equations

3. The attempt at a solution

My attempt. The meaning of {x:-4<x≤10} is that all the numbers of X, are greater than -4, and less than or equal to 10?

Interval notation of {x:-4<x≤10} = (-4,10]

Number line = -----(-4-----------0-----------------------10]

2. Jan 22, 2012

### Staff: Mentor

Looks fine.

3. Jan 22, 2012

### Johnyi

Is my meaning of {x:-4<x≤10} correct?

4. Jan 22, 2012

### genericusrnme

yes

(doesn't include
[does include

I like to think of it like the tops of the brackets are edging towards, but not reaching with the (, just like the set is edging towards but not reaching
With the square bracket you have it all there and it has reached there, just like the set

It sounds silly in words but that's how I remembered which meant what