Answer
$6b^2+7b-5$
Work Step by Step
Using $(a+b)(c+d)=ac+ad+bc+bd$ or the product of 2 binomials, the product of the given expression, $
(3b+5)(2b-1)
,$ is
\begin{array}{l}\require{cancel}
3b(2b)+3b(-1)+5(2b)+5(-1)
\\\\=
6b^2-3b+10b-5
\\\\=
6b^2+7b-5
.\end{array}
