keliling dan luas lingkaran yg berdiameter 42cm

42÷2=21
phi × r × r =
22/7 × 21 ×21 =
22×3×21=
66×21=1386
maaf kalo salah

Luas Lingkaran = π × r²
= 22/7 × 21²
= 22/7 × 441
= 1.386 cm²
Keliling Lingkaran = π × d
= 22/7 × 42
= 132 cm

Semoga Membantu :)
``»•^°Mystic°^•«``