Problems a through c are asking you what the values would be at those values.
What will the value of [tex]f(x)[/tex] be at [tex]x=0[/tex]? Let's look at the graph.
It seems at [tex]x=0[/tex], [tex]f(x)=0[/tex], meaning that [tex]f(0)=0[/tex]
Let's do the same for the others.
At [tex]x=-3[/tex], [tex]f(-3)=2[/tex]
At [tex]x=2[/tex], [tex]f(2)=-4[/tex]
For the last question, it is giving us the [tex]f(x)[/tex] value and asking us which [tex]x[/tex] values would give us that.
At [tex]f(x)=3[/tex], [tex]x=-2[/tex].
*Note* this function is continuous to the right, meaning that there is another point where [tex]f(x)=3[/tex].
Hope this helps.
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