fungsi f didefinisikan dengan rumus f(x) = px + q. jika f(-2) = -10 dan f(3) = 5 maka nilai f(-4) adalah....

jawab

f(x) = px + q
f(-2) = -10 --> -2p + q = - 10
f(3) = 5 .....--> 3p + q = 5..........(-)
-5p = - 15
p= 3

q = 5 - 3p = 5 - 3(3)
q = - 4

f(-4) = 3(-4) - 4 
f(-4) = -16

F(x) = px+q
F(-2)= -2p+q=-10
F(3)= 3p+q=5
________________ -
-5p = -15
p= 3

Masukkan nilai p=3 ke salah satu fungsi diatas:
F(-2) = -2p+q=-10
= -2×3 +q=-10
= -6+q=-10
= q = -10+6
= q = -4

Jadi F(x) = px+q
= 3x-4

Nilai F(-4) adalah:
F(x) = 3x-4
F(-4) = (3×-4) -4
F(-4) = -12-4
= -16