View source for Secant and tangent of a circle

A tangent is a line touching a circle in one point.  A secant is the line through two distinct points on a circle.

===Objectives===
To understand tangent and secant of a circle.

===Estimated Time===
30 minutes

===Prerequisites/Instructions, prior preparations, if any===
* The students should have a prior knowledge about a circle and its basic parts and terms.
* They should know the clear distinction between radius, diameter, chord, secant and tangent.

===Materials/ Resources needed===
* Digital : Computer, geogebra	application, projector.
* Non	digital : Worksheet	and pencil, compass, strings
* Geogebra	files :  [https://ggbm.at/mfeqt8w4 Lines	in a circle.ggb] 	
{{Geogebra|mfeqt8w4}}

===Process (How to do the activity)===
* The teacher can show the geogebra file.
* Move the points on circumference and explain secant.
* When both endpoints of secant meet, it becomes a tangent. 
* Name the points on the circumference of the circle.
* At how many points is the line touching the circle ?
* What is the line called ?

* '''Evaluation Questions''' 
# What is the difference between the secant and a tangent?
# What is the difference between the chord and a secant ? 
# Can you draw a secant touching 3 points on the circle ?
# At how many points does a tangent touch a circle ?
# How many tangents can be drawn to a circle ?
# How many tangents can be drawn to a circle at any one given point ?
# How many parallel tangents can a circle have at the most ?
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