tolong dengan caranya

cari jari-jari (r) = OB
Keliling lingkaran = 88 cm
=2πr
88 = 2 × 22/7 × r
88 = 44/7 × r
r= 7/44×88
r = 14 cm

AB² = AO² - OB²
= 50² - 14²
= 2500 - 196
= √ 2304 = 48
AB = 48 cm