Videos and lessons to help High School students learn how to construct a tangent line from a point outside a given circle to the circle.

Common Core: HSG-C.A.4

Related Topics:

Common
Core (Geometry)

Common Core
for Mathematics

How to draw the tangent lines to a circle when given a specific point outside the circle.

Tangent through a point not on a circle

How to use a compass to construct a line tangent to a circle and through a point NOT on the circle.

Tangents to a Circle

Tangents from a point outside a circle are congruent. Use the slider or drag the orange point to change the figure.

Tangents to a Circle from the Wolfram
Demonstrations Project by Jay Warendorff

Construction of Tangents to a circle

This applet shows how to construct tangents to a circle from a point outside the circle.

Drag the Step Slider to see each step

Drag point B to change the radius of the circle and explore what happens

- when the point A is inside the circle?

- when the point A coincides with point M?

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