tolong minta bantuanya ya

11] f(2) = 8x + k =15
8(2) + k =15
16 + k = 15
k = 15-16
k = -1

f(-1) = 8(-1) -1
= -8-1
= -9

f(0) = 8(0) -1
= 0-1
= -1

f(1) = 8(1) - 1
= 8-1
= 7

jadi, -9-1+7= -3


12] g(x)= 15-6x

g(a)= 15 - 6a= -3
-6a = -3 - 15
-6a = -18
a = 18/6
a = 3