mohon beserta caranya

Bab Kesebangunan
Matematika SMP Kelas VII

FE / DB = CE / EB
p / 12 = 5/15
p = 12 x 5 / 15
p = 4 

FE/AB = CE/BC
=> p/(p + 12) = 5/(5 + 15)
=> p/(p + 12) = 5/20
=> p × 20 = 5 × (p + 12)
=> 20p = 5p + 60
=> 20p - 5p = 60
=> 15p = 60
=> p = 60/15
=> p = 4
Jadi nilai p adalah 4