fungsi f ditanyakan dengan f[x+2]=8x-7.nilai f[5]adalah..... mohon bantuannya

f(x + 2) = 8x - 7
f(5) = ... ?

misal x + 2 = y
y = x + 2
x = y - 2

f(y) = 8(y - 2) - 7
= 8y - 16 - 7
= 8y - 23
f(x) = 8x - 23
f(5) = 8(5) - 23
= 40 - 23
= 17

f(x+2)=8x-7
f(5+2)=8*7-7
=56-7
=49