Diketahui keliling lingkaran 132cm,maka luas lingkaran adalah

K = πd
132 = 22/7 x d
d = 132 x 7/22
d = 42cm

r = d/2 = 42/2 = 21cm

L = πr²
L = 22/7 x 21 x 21
L = 1.386cm²

Keliling lingkaran
=Phi × diameter
= 22/7 ×... = 132 cm
= 7/22 × 132 cm
= 42 cm

Diameter = 42 cm
Jari jari (r) = 42 cm ÷ 2 = 21 cm



Luas lingkaran
= Phi × r²
= 22/7 × 21 cm × 21 cm
= 1.386 cm²



Semoga membantu ^^
Maaf kalau salah