diketahui rumus fungsi f(x)=6-2x. jika f(a)=-4 dan f(-1)=b, nilai a-b=

f(x) = 6-2x
f(a) = 6-2a = -4
-2a = -4-6 = -10
a = -10/-2 = 5

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

a-b = 5-8 = -3

Bab Fungsi
Matematika SMP Kelas VIII

f(x) = 6 - 2x
f(a) = 6 - 2a = -4
2a = 6 + 4
a = 10/2
a = 5

f(-1) = 6 - 2 . (-1) = b
b = 8

a - b = 5 - 8 = - 3