Ada yang bisa nomer 1,2&3 ? Tolong dong pake cara butuh banget

Nomor 1:
[tex] \frac{PR}{RT} = \frac{PQ}{ST} [/tex]
[tex] \frac{PR}{21} = \frac{7,5}{18} [/tex]
PR = [tex] \frac{21 . 7,5}{18} [/tex]
PR = 8,75 cm

Nomor 2:
[tex] \frac{CE}{CB} = \frac{DE}{AB} [/tex]
[tex] \frac{CE}{CE + BE} = \frac{30}{36} [/tex]
36 CE = 30 × (CE + 4)
36 CE = 30 CE + 120
36 CE - 30 CE = 120
6 CE = 120
CE = 20 cm

Nomor 3:
[tex] \frac{XY}{24} = \frac{WZ}{40} [/tex]
[tex] \frac{XY}{24} = \frac{15}{40} [/tex]
XY = [tex] \frac{24  .  15}{40} [/tex]
XY = 9 cm

[tex] \frac{WX}{32} = \frac{WZ}{40} [/tex]
[tex] \frac{WX}{32} = \frac{15}{40} [/tex]
WX = [tex] \frac{32  .  15}{40} [/tex]
WX = 12 cm
YZ = 12 cm

Keliling = WX + XY + YZ + WZ
Keliling = 12 + 9 + 12 + 15
Keliling = 48 cm