Intersection of two lines

Objectives
To verify vertically opposite angles are equal

Estimated Time
20 minutes

Prerequisites/Instructions, prior preparations, if any
Knowledge about point, line, angle

Materials/ Resources needed
Digital: Click here to open the file

Non-digital: Paper, pencil, ruler, compass, protractor

Process (How to do the activity)
Procedure :
 * 1) What are intersecting lines?
 * 2) Identify two lines cross each other in a plane i.e. lines 'g' and 'f' intersect at point 'A'
 * 3) Identify intersecting lines (two or more) meet only at one point always and also can cross each other at common vertex (which is the point of intersection).
 * 4) Identify the angles formed at common vertex 'A'
 * 5) Identify two pairs of opposite angles
 * 6) What is the vertically opposite angle?how many pair of vertically opposite angles are formed?
 * 7) Identify and measure vertically opposite angles?What is your conclusion?
 * 8) Can vertically opposite angles be adjacent?
 * 9) How many pairs of adjacent angles are formed?
 * 10) Idenify and measure adjacent angles?What is your conclusion?

Evaluation at the end of the activity
Go back - click here
 * 1) Can two lines cross at two points?
 * 2) If out of two angles of linear pair one is 60°, then what is the measure of other angle?
 * 3) If two angles are vertically opposite angles, where the measure of one of the angles is 30°, then what is the measure of other angle?