Answer
$b^2-7b+10$
Work Step by Step
Replacing $x$ with $b-2$ in the given function, $
f(x)=x^2-3x
$, then $f(b-2)$ is equal to
\begin{array}{l}
(b-2)^2-3(b-2)
\\\\=
(b)^2+2(b)(-2)+(-2)^2-3b+6
\\\\=
b^2-4b+4-3b+6
\\\\=
b^2+(-4b-3b)+(4+6)
\\\\=
b^2-7b+10
.\end{array}
