دائره مساحتها ٦٤ اوجد طول نصف قطرها ثم اوجد محيطها لاقرب عدد صحيح

A circle with an area of 64, find its diameter and circumference. The solution: the area of the circle equals π times the radius squared, so 64 = 3.14 × radius squared. Therefore, radius squared = 64 ÷ 3.14, radius squared = 20.38, radius = √20.38, radius = 4.5 cm. Secondly, the circumference of the circle equals 2π times the radius, so the circumference = 2 × 3.14 × 4.5. The circumference approximately equals 28.3 cm.