Respuesta :

Plug in all x's for 4.  4^2 = 16 --> 16x3=48 --> 48-7 = 41 
41 is the final answer
f(x)=3x²-7

Simply insert value of x, 4 into the equation then simplify
f(4)=3(4)
²-7
     =3(16)-7
     = 48 -7
     = 41