Just plug in 5 for 'x':
[tex]\sf 5\cdot (x-3)^2-7[/tex]
[tex]\sf 5\cdot (5-3)^2-7[/tex]
Parenthesis first, subtract:
[tex]\sf 5\cdot (2)^2-7[/tex]
Exponent next:
[tex]\sf 5\cdot 4-7[/tex]
Now multiplication:
[tex]\sf 20-7[/tex]
Finally, subtract:
[tex]\boxed{\sf 13}[/tex]
