To solve for p, we want to isolate the variable, so we divide both sides by 3:
3p/3 ā¤ -21/3
p ā¤ -7
To graph on the number line, we plot a closed circle at -7 and shade to the left of the circle to represent all the values that are less than or equal to -7.
[-8]---[-7]====================>
The solution is:
p ā¤ -7, or
The set of all real numbers less than or equal to -7.