Question

Diketahui rumus fungsi f(x) = ax + b. Jika f(1) = 1/6 dan f(-1) = 7/6. Nilai f(-2) = ...

A) -1
B) 0
C) 1
D) 2
E) 3

Answer 1

Verified answer

Kelas 8 Matematika
Bab Fungsi

f(x) = ax + b

f(1) = a + b = 1/6
f(-1) = -a + b = 7/6

-a + b = 7/6
 a + b = 1/6
----------------- -
-2a = 6/6
a = -1/2

a + b = 1/6
-1/2 + b = 1/6
b = 1/6 + 1/2
b = 1/6 + 3/6
b = 4/6
b = 2/3

f(x) = -1/2 x + 2/3
f(-2) = -1/2 . (-2) + 2/3
f(-2) = 1 + 2/3
f(-2) = 1 2/3