Answer
$3y^2-4y+2$
Work Step by Step
In symbols, the given statement is equivalent to
\begin{array}{l}\require{cancel}
7y^2-6y+5-(4y^2-2y+3)
.\end{array}
Removing the grouping symbols and then combining like terms, the expression abvoe simplifies to
\begin{array}{l}\require{cancel}
7y^2-6y+5-4y^2+2y-3
\\\\=
(7y^2-4y^2)+(-6y+2y)+(5-3)
\\\\=
3y^2-4y+2
.\end{array}