tolong jawab ya..mohon bantuannya

1. 16m dan 4m
2. 21m dan 35m
3. 14m
4. 0.5m, 7.5m, dan 1m
5. 24cm

1.)
AC = 20 meter
AB : BC = 4 : 1
* AB = (perbandingan AB / Total perbandingan)
x panjang keseluruhan
AB = (4/5) × 20 meter
AB = 16 meter

* BC = (1/5) × 20 meter
BC = 4 meter.

2.)
AB = 14 meter
AB : AC = 2 : 5
dit : BC dan AC = …?
* AC = (ditanya / diketahui) x diketahui
AC = (5/2) x 14 meter
AC = 35 meter

* BC = AC - AB
BC = (35 - 14) meter
BC = 21 meter

3.)
BC = 28 meter
AB = 1/5 AC
BC = 1 - 1/5
= 4/5
Maka :
AB = (ditanya/diket) x diketahui
= ((1/5) / (4/5)) x 28 meter [angka 5nya
dapat dicoret]
= (1/4) x 28 meter
= 7 meter

4.)
AB : BC : CD : DE = 3 : 1 : 5 : 2
AB = 1,5 meter
BC, CD, DE = …??

I. BC = (1/3) × 1,5 meter
= 0,5 meter

II. CD = (5/3) x 1,5
= 2,5 meter

III. DE = (2/3) x 1.5 meter
= 1 meter

5.)
panjang = 10cm
panjang : lebar = 5 : 1
lebar = (ditanya / diket) x diketahui
= (1/5) x 10cm
= 2cm
maka :
keliling = 2p + 2l
= 2(10) + 2(2)
= 20+4
= 24

semoga membantu :)))