Answer
a) Subtract 4, then square and add 3.
b) $f(2)=7$
$f(4)=3$
$f(6)=7$
Work Step by Step
a) Since the function is $f(x)=(x-4)^2+3$, in order to solve for a value, you must subtract 4 from it first, square it and then add three.
b) $f(2)=(2-4)^2+3=7$
$f(4)=(4-4)^2+3=3$
$f(6)=(6-4)^2+3=7$