Central Angles

Front

What is a central angle?

Back

A central angle is an angle whose vertex is at the center of a circle and whose sides are radii that extend to the circumference.

Front

What is a chord in a circle?

Back

A chord is a line segment whose endpoints lie on the circle.

Front

What is a secant line?

Back

A secant line is a line that intersects a circle at two points.

Front

What is a tangent line?

Back

A tangent line is a line that touches a circle at exactly one point.

Front

What is the relationship between a central angle and the arc it intercepts?

Back

The measure of a central angle is equal to the measure of the arc it intercepts.

Front

How do you calculate the area of a circle?

Back

The area of a circle is calculated using the formula A = πr², where r is the radius.

Front

What is the measure of a semicircle?

Back

The measure of a semicircle is 180 degrees.

Front

If the measure of arc AB is 142 degrees, what is the measure of the central angle that intercepts arc AB?

Back

The measure of the central angle that intercepts arc AB is also 142 degrees.

Front

What is the formula for the circumference of a circle?

Back

The circumference of a circle is calculated using the formula C = 2πr, where r is the radius.

Front

What is the relationship between the angles formed by two tangents drawn from a point outside the circle?

Back

The angle formed by two tangents drawn from a point outside the circle is equal to half the difference of the measures of the intercepted arcs.