Jawabanmu

2014-03-05T20:10:29+07:00
L = 22/7 x r²
38,5 x 7/22 = r²
12,25 = r²
r = 3,5
K = 2 x 3,5 x 22/7 = 22
<POQ = (Busur PQ / Keliling) x 360°
           = (5,5 / 22) x 360 = 90°
2014-03-05T20:12:46+07:00
L = 22/7 x r²
38,5 x 7/22 = r²
12,25 = r²
r = 3,5

K = 2 x 3,5 x 22/7 = 22
<POQ = (Busur PQ / Keliling) x 360°
           = (5,5 / 22) x 360 = 90°