**Understanding Elementary Shapes**

**Question 1.Which of the following are models for perpendicular lines:**

**(a)**The adjacent edges of a table top.

**(b)**The lines of a railway track.

**(c)**The line segments forming the letter ‘L’.

**(d)**The letter V.

**Solution:****(a)** Yes**(b)** No**(c)** Yes**(d)** No

**Question 2.Let be the perpendicular to the line segment . Let and intersect in the point A. What is the measure of ∠PAY?**

**Solution:**

The measure of ∠PAY =90° [∵ PQ ⊥ XY, given]

**Question 3.There are two “set-squares” in your box. What are the measures of the angles that are formed at their corners? Do they have any angle measure that is common?**

**Solution:**

In one, the angles are of 30°, 60°, 90° and in the other the angles are of 90°, 45°, 45°.

Clearly, the common angle = 90°

**Question 4.Study the diagram. The line l is perpendicular to line m.**

**(a)**Is CE = EG?

**(b)**Does PE bisect CG?

**(c)**Identify any two line segments for which PE is the perpendicular bisector. ‘ ’

**(d)**Are these true?

**(i)**AC > FG

**(ii)**CD = GH

**(iii)**BC< EH

**Solution:**