Answer
a) $f(2)=5$
b) $f(-1)=11$
Work Step by Step
a) When $x=2,$ the corresponding $y-$value in the given set of ordered pairs is $
5
.$ Hence,
\begin{array}{l}\require{cancel}
f(2)=5
.\end{array}
b) When $x=-1,$ the corresponding $y-$value in the given set of ordered pairs is $
11
.$ Hence,
\begin{array}{l}\require{cancel}
f(-1)=11
.\end{array}