Question 1209112
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5x-7 < 2x+5
5x-2x < 5+7
3x < 12
x < 12/3
<font color=red>x < 4</font>


To solve what is shown above, we get all the x terms to one side while everything else is to the other side. 
When we divide both sides by a positive number, it does not flip the inequality sign.


x < 4 in interval notation is <font color=red>(-infinity, 4)</font>
You can think of x < 4 as -infinity < x < 4
Replace the word "infinity" with the symbol if needed.


The graph of x < 4 on a number line has an <font color=red>open hole at 4</font> and <font color=red>shading to the left.</font>
This is to visually represent all numbers smaller than 4.
The open hole means "exclude this endpoint from the solution set".
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