diketahui fungsi f(x) = ax + b . jika f(4) = -2 dan f(-4) = 6 ,nilai f(8)

Langsung aja y

f(4) = 4a + b = -2
f(-4) = -4a + b = 6
_____________-
8a = -8
a = -1

4a + b = -2
b = -2 - 4(-1)
b = -2 + 4
b = 2

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

f(8) = -8 + 2
f(8) = -6

Semoga berguna +_+

-4a + b = 6
4a + b = -2
_________ +
2b = 4
b = 2

substitusikan b=2

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

f(8)
= ax + b
= -1(8) + 2
= -8 + 2
= -6

jadi f(8) = -6