Me ! what does the line mean under the < thing. what does it mean if the dot is all black vs./2 not filled also my question mark isn't working if that makes it less confusing

The line under means equal too... on this example it means less than or equal to.  It mean you will include the 3.  If there is not a line it means you would not include the 3.

The open circle and closed circle in the graph means:

open circle means: less than or greater than

closed circle means: less than or equal to greater than or equal to.

The line under the < thing is called "less or equals to". So if the dot is black, it means that it is less of equals to the certain number. If there is no line under <, it means that the number is less than the number.

It said that x is less or equals to 3 so the arrow on the line should head towards the left. The dot on the line should be a black dot since x ≤ 3. So your answer should be the third number line.

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