Kalau bisa no11 dan 12 Pakai caranya ya?

11. 14cm = radius lingkaran
keliling satu lingkaran pi x Diameter = 22/7 x 28 = 88cm
88 cm x 3/4 =66cm
66cm + 28 = 94 cm

luas =
lingkaran --> pi x r^2
22/7 x 7 x 7 = 154 cm^2
154 x 3/4 = 115,5 cm^2
luas kotak --> 14 x 14 = 196 cm^2
luas total = 115.5 + 196 = 311.5 cm^2

12. AOB = 180-135 = 45 derajat
AOB = 2x ADB
ADB = 45/2 = 22,5 derajat