lingkaran dgn diameter 7 cm maka luas lingkaran tsb adalah...cm² a.36,5 c.77 b.38,5 d.77,46 plis jawab

d = 7
r = 1/2 * d
r = 1/2 * 7 = 3.5
π = 22/7

Luas Lingkaran = π * r * r  
                          =22/7 * 3.5 * 3.5 
                          =38.5

Jawabanya B. 38.5

d = 7 cm
r = 3.5 cm
[tex]\pi \: = \frac{22}{7} [/tex]

dit: luas lingkaran?

luas lingkaran =
[tex]\pi {r}^{2} [/tex]
maka :
[tex] \frac{22}{7} \times 3.5 \times 3.5 \\ = \frac{22}{7} \times 12.25 \\ = 38.5[/tex]