Test Review on Circles

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where r is the radius.

Front

Define an inscribed angle in a circle.

Back

An inscribed angle is formed by two chords in a circle which have a common endpoint.

Front

What is the relationship between the inscribed angle and the arc it intercepts?

Back

The inscribed angle is half the measure of the intercepted arc.

Front

What is the equation of a circle in standard form?

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 of a circle from its equation?

Back

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

Front

What does it mean for a line to be tangent to a circle?

Back

A tangent line touches the circle at exactly one point.

Front

How can you determine if a line is tangent to a circle?

Back

If the distance from the center of the circle to the line equals the radius, the line is tangent.

Front

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

Back

The center is (-3, 2).

Front

What is the arc length formula?

Back

Arc length = (θ/360) * 2πr, where θ is the central angle in degrees.

Front

How do you calculate the area of a circle?

Back

Area = πr², where r is the radius.