bantu jawab no.5&2 ya yg bisa. makasi

Bab Lingkaran

5. Panjang tali minimal
= Keliling + Banyak lingkaran × diameter
= πd + n × d
= d(n + π)
= 7 cm(3 + 22/7)
= 7 cm(21/7 + 22/7)
= 7 cm(43/7)
= 43 cm

2. r1 : r2 = 1 : 2
Misalkan
r1 = x
r2 = 2x

d^2 = p^2 - (r1 + r2)^2
8^2 = 10^2 - (x + 2x)^2
64 = 100 - (3x)^2
(3x)^2 = 100 - 64
3x = √36
x = 6/3
x = 2

r1 = 2 cm
r2 = 2(2) = 4 cm