Question

The circle below is centered at the origin and has a radius of 10. What is its equation?

Answer 1

x^2 + y^2 = 10^2

Explanation:

So the center of the circle is (0, 0).

x^2 + y^2 = 10^2

Answer 2

x² + y² = 100

Explanation:

The equation of a circle is (x - h)² + (y - k)² = r²

• Here our center, (h, k), is (0,0)
• The radius is 10

Plugging in these values to the equation of a circle we get:

• (x - 0)² + (y - 0)² = (10)²
• This then simplifies to x² + y² = 100