Question

Dik luas lingkaran 1256cm
dit. keliling lingkaran

Answer 1

L = π r²
r² = L/π
   = 1256 / 3,14
  = 400
r = √400
  = 20 cm

K = 2 π r
   = 2 x 3,14 x 20
  = 125,6 cm

Jadi Kelilingnya yaitu 125,6 cm²

Answer 2

L = πr²
1256 = 3,14 x r²
r² = 1256/3,14
r² = 400
r = √400
r = 20

Maka;
K = 2πr
K = 2 x 3,14 x 20
K = 125,6 cm