tolong ya jawab pake caranya...... please!!!

A.
a² + a² = (√32)²
2a² = 32
  a² = 32/2
 a² = 16
a = √16
a = 4

B.
b/r = Cos 30°
b = r. Cos 30°
b = 16 (1/2 √3)
b = 8√3