Since the problem states to substract from the second polynomial given the problem that we will be solving is
[tex](7x^2+6x)-(2x-3)^2[/tex]
continue by solving the expression that is squared using the definition
[tex](a-b)^2=a^2-2\cdot a\cdot b+b^2[/tex]
applying this to the expression given
[tex]\begin{gathered} (2x-3)^2=(2x)^2-2\cdot(2x)\cdot(3)+(3)^2 \\ (2x-3)^2=4x^2-12x+9 \end{gathered}[/tex]
insert this into the first expression
[tex]\begin{gathered} (7x^2+6x)-(2x-3)^2 \\ (7x^2+6x)-(4x^2-12x+9) \end{gathered}[/tex]
distribute the negative sign
[tex](7x^2+6x)-4x^2+12x-9[/tex]
simplify the expression
[tex]3x^2+18x-9[/tex]
