tolong yah kaka minta bantuan nya

Diketahui :
DE // AB
CD = 8 cm
AD = 2 cm
DE = 4 cm

Ditanyakan :
AB = ...?
BE : BC = ...?

Penyelesaian :
AB/DE = AC/CD
<=> AB/4 = (2+8)/8
<=> AB/4 = 10/8
<=> 8AB = 40
<=> AB = 40/8
<=> AB = 5 cm

BE/BC = AD/AC
<=> BE/BC = 2/(2+8)
<=> BE/BC = 2/10
<=> BE/BC = 1/5
<=> BE : BC = 1 : 5

de/ab = cd/ac
4/ ab = 8 / 10
40 = 8 ab
40/ 8 = ab
5 = ab

perbandingan
Be ÷ bc = ...
jika bc= ac = 10 cm
& Be = da = 2 cm
maka,
be ÷ bc = 2 ÷ 10 = 1 ÷ 5