Equations of Circles, Tangents and Secants

In the equation (x+2)²+(y-3)²=4, the radius of the circle is...

• 4

• 2

• 3

• 16

Write the standard equation of the circle with the given center and radius; center (0,0) and radius: 3

• x²+y²=3

• x²+y²=6

• x²+y²=9

The diameter of a circle has length 12. The center is at (-5, 2). Give the equation of the circle.

• (x - 2)² + (y + 5)² = 36

• (x - 5)² + (y + 2)² = 6

• (x + 5)² + (y - 2)² = 36

• (x + 2)² + (y - 5)² = 6

What is the diameter?

• 8

• 16

• 10

• 4

In the figure,PA and PB are the tangents to a circle of center 'O'. ∠AOB= 120⁰ then ∠APB =

• 60⁰

• 30⁰

• 120⁰

• 75⁰

In the figure,PA and PB are the tangents to a circle of centre 'O'. If ∠APB = 48⁰ then ∠AOP =

• 68⁰

• 66⁰

• 56⁰

• 76⁰

In the figure,PA and PB are the tangents to a circle of centre 'O'. If ∠AOP = 45⁰ then ∠APB =

• 65⁰

• 135⁰

• 90⁰

• 22.5⁰

What is the definition of a tangent?

• A line that intersects the circle on two points.

• A line that passes through the center of the circle.

• A line segment that passes through the center of the circle.

• A line that intersects the circle on only one point.

What can you conclude from the picture?

• m is parallel to circle C

• m is skew to circle C

• m bisects circle C

• m is tangent to circle C

A tangent to a circle is ________________________ to the radius drawn to the point of tangency.

• congruent

• perpendicular

• complimentary

• supplementary