Question

Diketahui f(x) = ax + b. jika f(1) = -1 dan f(3) = 5 maka f(-2) adalah

Answer 1

Cari nilai a :
( 5 + 1 ) : ( 3 - 1 ) = 3

Cari nilai b :
f(1) = -1
  -1 = 3(1) + b
  -1 = 3 + b
   b = 3 + 1
   b = 4

Maka,
f(-2) = 3(-2) + 4
        = -6 + 4
        = -2