diketahui fungsi f(x) =px +q jika f(-1)=1 dan f(5)=13 maka f(3) adalah

f(-1) = -1p + q = 1
f(5) = 5p + q = 13 -
-6p = -12
p = 2
-1p + q = 1
-2 + q = 1
q = 3
f(3) = 2(3) + 3 = 9

f(x) = px + q

f(-1) = p(-1) + q = 1
f(5) = p(5) + q = 13
(dikurangkan)
-6p = -12
p = -12/-6
p = 2

subtitusikan ke
f(5) = 2.5 + q = 13
q = 13 - 10 = 3

f(3) = 2.3 + 3
= 6 + 3
= 9