Question

State the radius of this circle:
X^2 +Y^2=121

Answer 1

radius = 11

Explanation:

The equation of a circle centred at the origin is

x² + y² = r² ( where r is the radius )

x² + y² = 121 ← is the equation of a circle centred at the origin

with r² = 121 , then

r =
`√(121)` = 11