#### Answer

(a) $f(2)=2$
(b) $f(-1) = 3$

#### Work Step by Step

(a) The value of $f(2)$ is the second coordinate of the ordered pair whose first coordinate is $2$.
The function contains the point $(2, 2)$.
Thus, $f(2) = 2$.
(b) The value of $f(-1)$ is the second coordinate of the ordered pair whose first coordinate is $-1$.
The function contains the point $(-1, 3)$.
Thus, $f(-1) = 3$.