Secant and tangent of a circle

=Activity - Understanding secant and tangent using Geogebra=

Estimated Time
40 minutes

Prerequisites/Instructions, if any

 * 1) The students should have a prior knowledge about a circle and its basic parts and terms.
 * 2) They should know the clear distinction between radius, diameter, chord, secant and tangent.

Multimedia resources
Laptop, geogebra file, projector and a pointer.

Website interactives/ links/ simulations/Geogebra applets
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enableRightClick="false" showAlgebraInput="false" enableShiftDragZoom="true" showMenuBar="false" showToolBar="false" showToolBarHelp="true" enableLabelDrags="false" showResetIcon="true" />

Process (How to do the activity)

 * 1) The teacher can show the geogebra file.
 * 2) Move the points on circumference and explain secant.
 * 3) When both endpoints of secant meet, it becomes a tangent.

Developmental Questions (What discussion questions)

 * 1) Name the points on the circumference of the circle.
 * 2) At how many points is the line touching the circle ?
 * 3) What is the line called ?

Evaluation (Questions for assessment of the child)

 * 1) What is the difference between the secant and a tangent?
 * 2) What is the difference between the chord and a secant ?

Question Corner

 * 1) Can you draw a secant touching 3 points on the circle ?
 * 2) At how many points does a tangent touch a circle ?
 * 3) How many tangents can be drawn to a circle ?
 * 4) How many tangents can be drawn to a circle at any one given point ?
 * 5) How many parallel tangents can a circle have at the most ?

Activity Keywords

 * 1) Geogebra
 * 2) Secant
 * 3) Tangent

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