Construct an isosceles trapezium and study its properties


 * Estimated Time: 40 minutes.
 * Materials/ Resources needed: Laptop, geogebra file, projector and a pointer.
 * Prerequisites/Instructions, if any
 * 1) The students should know the concepts of parallel lines, perpendicular lines and rectangle.
 * 2) They should know basic constructions like parallel lines and perpendicular lines.
 * Multimedia resources: Laptop.
 * Website interactives/ links/ / Geogebra Applets : This geogebra file has been done by ITfC-Edu-Team
 * Process:
 * 1) Recall the figure trapezium and its properties.
 * 2) State that a trapezium with two non- parallel sides equal is an isosceles trapezium.
 * 3) By moving the vertices of the trapezium, you can observe trapeziums of different sizes and shapes.
 * 4) Make sure you note when your trapezium turns into a rectangle.
 * 5) Observe the symmetry of an isosceles trapezium.
 * 6) Study its properties.
 * 7) Drag the vertices of the trapezium and observe your angle measures.
 * 8) Make a conjecture about the base angles of an isosceles trapezium. (Both of the parallel sides are considered bases, so a trapezium has two pairs of base angles.)
 * Developmental Questions:
 * 1) What are parallel lines ?
 * 2) What is a trapezium ?
 * 3) Is trapezium a quadrilateral ?
 * 4) What are the characteristic properties of a trapezium ?
 * 5) What do you notice about the non-parallel sides ?
 * 6) How many interior angles do you see ?
 * 7) What is the sum of 4 angles of any quadrilateral ?
 * 8) What can you conclude about interior angles ?
 * 9) What is special about diagnols in an isosceles trapezium ?
 * Evaluation:
 * 1) Are all trapeziums isosceles ?
 * 2) Are all trapeziums quadrilaterals too ?
 * 3) Can rectangle be considered as an isosceles trapezium ?
 * Question Corner:
 * 1) State the properties of isosceles trapezium ?