UNIT 9 CIRCLES - Some Review

Front

What is an arc in a circle?

Back

An arc is a portion of the circumference of a circle.

Front

What is a major arc?

Back

A major arc is an arc that measures more than 180 degrees.

Front

What is a minor arc?

Back

A minor arc is an arc that measures less than 180 degrees.

Front

What is a semicircle?

Back

A semicircle is an arc that measures exactly 180 degrees.

Front

What is the formula for the area of a sector?

Back

Area of a sector = (θ/360) × πr², where θ is the angle in degrees and r is the radius.

Front

What is the diameter of a circle?

Back

The diameter is a straight line passing from side to side through the center of a circle, equal to twice the radius.

Front

What is a radius?

Back

A radius is a line segment from the center of a circle to any point on its circumference.

Front

What is a tangent line?

Back

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

Front

What is a secant line?

Back

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

Front

How do you find the measure of an arc?

Back

The measure of an arc can be found using the central angle that subtends the arc.