Circles, arcs, angles

Front

What is the definition of a circle?

Back

A circle is a set of points in a plane that are equidistant from a fixed point called the center.

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr, where r is the radius.

Front

What is the relationship between the diameter and radius of a circle?

Back

The diameter is twice the radius (Diameter = 2 × Radius).

Front

What is an arc in a circle?

Back

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

Front

What is the measure of a full angle in degrees?

Back

A full angle measures 360 degrees.

Front

What is a central angle?

Back

A central angle is an angle whose vertex is at the center of the circle and whose sides are radii.

Front

What is the inscribed angle theorem?

Back

The inscribed angle is half the measure of the central angle that subtends the same arc.

Front

What is a cyclic quadrilateral?

Back

A cyclic quadrilateral is a four-sided figure where all vertices lie on the circumference of a circle.

Front

What is the sum of the opposite angles in a cyclic quadrilateral?

Back

The sum of the opposite angles in a cyclic quadrilateral is 180 degrees.

Front

What is the formula for the area of a circle?

Back

Area = πr², where r is the radius.