Tentukan panjang OA dan luas segitiga OAB! tolong ya kak… besok harus dikumpulin…

A.) OA = OB = r
L.3/4 lngkrn = 3/4× π × r^2
942 = 3/4 × π× r^2
π × r^2 = 942 : 3/4
π × r^2 = 942× 4/3
π × r^2 = 1256
r^2 = 1256 : π
r^2 = 1256 : 3,14
r^2 = 1256 : 314/100
r^2 = 1256 × 100/314
r^2 = 125600/314
r^2 = 400
r = √400
r = 20 cm
jd,OA = OB = 20 cm

b.) a = t = r = 20 cm
L segtg AOB = 1/2 × a × t
= 1/2 × 20 × 20
= 1/2 × 400
= 400/2
= 200 cm^2