Suatu fungsi f : x → p - 4x. Tentukan : a. nilai p jika (f-1) = 8 b. nilai dari f(-7) c. nilai a jika f(a) = -12

1. F(x) = p-4x
f(-1) = p-4(-1)
8 = p-(-4)
8 = p+4
8-4 = p
p = 4
2. F(-7) = p-4(-7)
f(-7) = 4-(-28)
f(-7) = 4+28
f(-7) = 32
3. F(a) = p-4a
-12 = 4-4a
-12-4 = -4a
-4a = -16
a = -16/-4
a = 4

a. f(-1) = p - 4.-1
f(1) = p - 4
p = 5
b. f (-7) = p - 4.-4
-7 = p-16
f(-7) = 9 - 16