tolong no. 12 13 14 dgn cara ya..

F(x)=6x + k
F(-1)= -1 x 6 + k =2
-6 + k = 2
K = 2 + 6
K = 8

F(x)= 6x + 8 (A)

2 ( p+l ) = Keliling
2( p + 20) = 100
2p + 40 = 100
2p = 100 - 40
2p = 60
p = 60/2
p = 30

Luas = p x l
= 30 x 20
= 600 (B)