Introduction to Functions and Graphs

When $x=5$, $f(5)=3(5)+2=3\times 5+2=17$.

When $x=2$, $f(2)=4(2)-3=8-3=5$.

The 3 inside the brackets means we are replacing $x$ with the value 3. So, $f(3)=2(3)-4=2\times 3-4=2$.

Substitute 7 for $f(x)$, so we have the equation: $7=3x-5$. First, add 5 to both sides to get $12=3x$. Then, divide both sides by 3 to find $x=4$.

To find $f(-2)$, substitute $x=-2$ into the function. So, $f(-2)=5(-2)+8=-10+8=-2$.

From the graph, we can see that the function intersects the horizontal line $f(x)=-3$ at $x=4$ and $x=-2$. Therefore, the correct answer is 4 and -2.