Respuesta :

Step-by-step explanation:

4 lies in the interval

[tex]1 < x \leqslant 5 \\ \therefore \: f(x) = x - 7 \\ \therefore \: f(4) = 4 - 7 \\ \\ \huge \red{ \boxed{ \therefore \: f(4) = - 3}}[/tex]