Answer:
[tex]{ \tt{f(x) = - {x}^{2} + 6x - 18}}[/tex]
• when f(x) is f(-3), then x is -3. Substitute for x as -3:
[tex]{ \sf{f( - 3) = - {( - 3)}^{2} + 6( - 3) - 18 }} \\ \\ { \sf{f( - 3) = - 9 - 18 - 18}} \\ \\ \dashrightarrow \: { \boxed{ \tt{f( - 3) = - 45}}}[/tex]
