Jawabanmu

2014-05-19T15:55:18+07:00
Keliling = 2 π r
176 =  2x 22 x r
               7
r = 28
 luas = 22 x 28 x28
           7
= 2464

2014-05-19T16:01:54+07:00
176 = 2 x 22/7 x r <=> 176 = 44/7 x r <=> r = 7 x 176/44 = 28 cm
maka, luas lingkaran = π r² = 22/7 x 28 x 28 = 2464 cm²    {semoga membantu :D }