Jawabin ya :)……………​

13.

Persekutuan luar (l) = √jarak kedua lingkaran² (p)² – (Jari jari besar (R) – Jari jari kecil (r) )

l = √p² – (R – r)²

l = √17² – (12 – 4)²

l = √289 – (8)²

l = √289 – 64

l = √225

l = 15 Cm

14.

Persekutuan dalam (d) = √p² – (R+r)²

d = √7,5² – (2,5 + 2)²

d = √56,25 – (4,5)²

d = √56,25 – 20,25

d = √36

d = 6 Cm

15.

R = r + √p² – l²

R = 3 Cm + √13² – 12²

R = 3 Cm + √169 – 144

R = 3 Cm + √25 Cm

R = 3 Cm + 5 Cm

R = 8 Cm