Tentukan luas dan keliling lingkaran jika diameter nya 28 cm

Pembahasan :

Luas lingkaran
[tex] = \pi \times {r}^{2} \\ = \frac{22}{7} \times 14 \times 14 \\ = 616 \: \: {cm}^{2} [/tex]

Keliling lingkaran
[tex] = \pi \times d \\ = \frac{22}{7} \times 28 \\ = 88 \: \: {cm}^{2} [/tex]

Good Luck ^^

[tex]luas \: = \: \pi \: \times {r }^{2} \\ luas = \frac{22}{7} \times 14 \times 14 = 616 {cm}^{2} \\ k = 2 \times \pi \times r \\ k = 2 \times \frac{22}{7} \times 14 = 88 \: cm[/tex]