Suatu fungsi dinyatakan dengan f(x) = ax b. Jika f(2) = 1 dan f(-2) = -11 maka nilai f(-5) =

MAPEL = MATEMATIKA
KELAS = 8
BAB = RELASI & FUNGSI

diketahui =
f(x) = ax + b
f(2) = 1
f(-2) = -11

ditanya = nilai f(-5) ??

f(x) = ax + b = 1
f(2) = 2a + b = 1

f(x) = ax + b = -11
f(-2) = -2a + b = -11

eliminasi nilai b
2a + b = 1
-2a + b = -11
__________-
3a = 12
a = 12/3
a = 4

subtitusi nilai a
2a + b = 1
2(4) + b = 1
8 + b = 1
b = 1 - 8
b = -7

rumus fungsi
➡ f(x) = ax + b
➡ f(x) = 4x - 7

nilai f(-5)
f(x) = 4x - 7
f(-5) = 4(-5) - 7
f(-5) = -20 - 7
f(-5) = -27

semoga membantu

Jangan Lupa Jadiin Jawaban Terbaik Dan Jangan Lupa Follow;)
Trims