Nomor 2 Kak Minta bantuan Ya Kak...

2)
AB//DE
AD = 3 cm
CD = 9 cm
CE = 12 cm
BE = x

AD/(AD + CD) = BE/(BE + CE)
3/(3 + 9) = x/(x + 12)
3/12 = x/(x + 12)
3 × (x + 12) = x × 12
3x + 36 = 12x
12x - 3x = 36
9x = 36
x = 36/9
x = 4

Jadi panjang x adalah 4 cm