Keliling lingkaran 62,8, maka luas lingkaran tersebut

K ○ = phi d
62,8 = 3,14 × d
62,8/3,14 = d
d = 20 cm

r = d/2
= 20/2
= 10
L ○ = phi r2
= 3,14 × 10 × 10
= 314
Semoga membantu

K = 2×phi×r=62,8
K = 2×3,14×r=62,8
K = 6,28r=62,8
K = r = 62,8/6,28
K = r = 10

L = phi×r²
L = 3,14×10²
L = 314