Question

find equation of the circle whose centre is (-4,5) and circumference is 8π units​

Answer 1

Answer:

Circumference, 2πr = 16π  ⇒ 2r = 16  ⇒ r = 8  Equation of the circle when centre and radius are known is (x – h)2 + (y – k)2 = r2  ⇒ (x + 3)2 + (y + 2)2 = 82  ⇒ x2 + 6x + 9 + y2 + 4y + 4 = 64 ⇒ x2 + y2 + 6x + 4y + 13 = 64  ⇒ x2 + y2 + 6x + 4y – 51 = 0Read more on Sarthaks.com - https://www.sarthaks.com/979763/find-the-equation-of-the-circle-whose-centre-is-3-2-and-having-circumference-16