Circles: Secants and Tangents

Front

What is 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

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

Front

What is the area of a circle?

Back

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

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 radius and a tangent?

Back

A radius drawn to the point of tangency is perpendicular to the tangent line.

Front

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

Back

The center of the circle is (3, 2).

Front

How many degrees are in a full circle?

Back

There are 360 degrees in a full circle.

Front

What is the radius of a circle if the equation is (x-5)²+(y+1)²=36?

Back

The radius of the circle is 6.

Front

What is the diameter of a circle?

Back

The diameter is twice the radius of the circle.