diketahui fungsi f(x)=ax-8,jika f(4)=-7,tentukan nilai a

f(x) = ax - 8
f(4) = 4a - 8
 -7  = 4a - 8
 4a = -7 + 8
4a  = 1
  a  = 1/4

f(4)=a(4) - 8
-7 =4a - 8
1=4a
a=1/4