tolong pake caranya yaa no 11

p = (3x + 5)
l = (x + 6)
K = 54 cm

Keliling persegi panjang
K = 2p + 2l
K = ( 2 x (3x + 5) ) + ( 2 x (x + 6) )
54 = ( 6x + 10 ) + ( 2x + 12)
54 = 8x + 22
54 - 22 = 8x
32 = 8x
x = 4

subtitusikan x = 4
p = (3x + 5)
p = 3 x (4) + 5
p = 12 + 5
p = 17 cm

l = (x + 6)
l = (4 + 6)
l = 10 cm

jawabannya adalah B