C = 2\pi r = 2\pi \times 8.5 = 17\pi \text{ cm}

Thu, 16 Apr 2026 10:52:07 +0000

Understanding the Formula C = 2πr and Its Application: Complete Circumference Calculation for a Circle with Radius 8.5 cm When studying geometry, one of the most fundamental and frequently used equations is the circumference formula: C = 2πr where C is the circumference, r is the radius, and π (pi) is a mathematical constant approximately equal to 3.14159. This formula calculates the total distance around a circle and is essential in fields ranging from architecture to engineering and even everyday measurements.