Diketahui fungsi linear f(×) = pq + q dgn nilai f(2) = 1 Dan f(3) =-1 . Nilai f(6) adalah

f(x) = px + q

f(2) = 2p + q = 1
f(3) = 3p + q = -1
       ------------------ (-)
            p = -2

subtitusi
2p + q = 1
2(-2) + q = 1
q = 1 + 4
q = 5

rumus fungsi f
f(x) = -2x + 5

f(6) = -2(6) + 5
f(6) = -12 + 5
f(6) = -7