Unit 7.1 Equation of a Circle

Front

What is the standard form of the equation of a circle?

Back

(x - h)² + (y - k)² = r², where (h, k) is the center and r is the radius.

Front

How do you find the radius from the equation of a circle?

Back

The radius is the square root of the constant on the right side of the equation in standard form.

Front

What is the center of the circle in the equation (x - 3)² + (y + 2)² = 16?

Back

(3, -2)

Front

What does the term 'circumference' refer to in relation to a circle?

Back

The distance around a circle.

Front

If the radius of a circle is 5, what is the equation of the circle?

Back

(x - h)² + (y - k)² = 25, where (h, k) is the center.

Front

What is the radius of the circle with the equation (x - 1)² + (y + 3)² = 9?

Back

3 (since the radius is √9).

Front

How do you determine the center of a circle from its equation?

Back

The center is found at the point (h, k) from the equation (x - h)² + (y - k)² = r².

Front

What is the circumference of a circle with a radius of 4?

Back

Circumference = 2πr = 8π.

Front

What is the area of a circle with a radius of 2?

Back

Area = πr² = 4π.

Front

What does 'r' represent in the equation of a circle?

Back

'r' represents the radius of the circle.