Penjelasan dengan langkah-langkah:

1.a. jari-jari = OD ,OC ,OA,OB

b. tali busur= CD,CA,AB(jika di tarik garis,maka namanya tali busur)

c.busur lingkaran=BD(garis tepi pd bagian lingkaran)

d.tembereng lingkaran=CD (bagian yg di arsir) e. juring lingkaran=OAB (daerah yg di arsir)

2. Kelililing lingkaran= 2 × Π ×r

a. r =6 cm

k =>2 × 3,14 × 6

k = 37,68 cm

b. d = 42 cm

r = d:2= 42:2

r =21 cm

K => (2 × 22/7 )× 21

= 44/7 × 21

= 132 cm

c. d = 45

r = 45 : 2= 22,5 cm

K = 2 × 3,14 × 22,5 = 141,3

d. r = 36 cm

K = 2 ×3,14 × 36 = 226,08 cm

3. Luas lingkaran = Π × r × r

a. r = 42

L = (22/7 ×42) ×42

=132× 42= 5544 cm²

b. d = 50 cm

r = 50:2=25 cm

L = 3,14 ×25 ×25

=1962,5 cm²

4. K =198 m maka

d =k:Π

d=198:22/7 = 63 cm. maka,r = 63:2=31,5

L =Π×r×r =22/7×31,5×31,5

=3118,5