Answer
$3m^2+28m+9$.
Work Step by Step
The given expression is
$=(3m+1)(m+9)$
Distribute $(m+9)$ to each term of $(3m+1)$.
$=3m(m+9)+1(m+9)$
Use distributive property.
$=3m(m)+3m(9)+1(m)+1(9)$
Multiply.
$=3m^2+27m+m+9$
Combine like terms.
$=3m^2+28m+9$
Hence, the product is $3m^2+28m+9$.
