Construct Tangent to a Circle

Common Core: HSG-C.A.4

Construction - Tangent to a Circle From a Point Outside the Circle
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.


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?

Try out our new and fun Fraction Concoction Game.

Add and subtract fractions to make exciting fraction concoctions following a recipe. There are four levels of difficulty: Easy, medium, hard and insane. Practice the basics of fraction addition and subtraction or challenge yourself with the insane level.

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