tentukan keliling dan luas lingkaran jika diketahui: A.jari-jari lingkaran 28cm B.diameter lingkaran 40cm

Penjelasan dengan langkah-langkah:

A

K = 2 π r

K = 2 × 22/7 × 28

K = 2 × 22 × 4

K = 176 cm

L = π r²

L = 22/7 × 28 × 28

L = 22 × 4 × 28

L = 2.464 cm²

B

K = π d

K = 3,14 × 40

K = 125,6 cm

L = π r²

L = 3,14 × 40 × 40

L = 5.024 cm²

Penjelasan dengan langkah-langkah:

A. K=1/2×ll×r

=1/2×3,14×28

=3,14×14

=43,96

L=llr²

=22/7×28×28

=22×4×28

=88×28

=2.464

B.

K=1/2×ll×r

=1/2×3,14×20

=3,14×10

=31,4

L=llr²

=3,14×20×20

=3,14×400

=1.256