NCERT Solutions Ganita Prakash (Part 2) Chapter 1 Figure it Out (4)

ΔAIR ≅ ΔFLY. Identify the corresponding vertices, sides and angles.

Each of the following cases contains certain measurements taken from two triangles. Identify the pairs in which the triangles are congruent to each other, with reason. Express the congruence whenever they are congruent. (a) AB = DE (b) AB = EF BC = EF ∠A = ∠E CA = DF AC = ED (c) AB = DF (d) ∠A = ∠D ∠B = ∠D = 90° ∠B = ∠E AC = FE AC = DF (e) AB = DF ∠B = ∠F AC = DE

It is given that OB = OC, and OA = OD. Show that AB is parallel to CD. [Hint: AD is a transversal for these two lines. Are there any equal alternate angles?]

ABCD is a square. Show that ΔABC ≅ ΔADC. Is ΔABC also congruent to ΔCDA? Give more examples of two triangles where one triangle is congruent to the other in two different ways, as in the case above. Can you give an example of two triangles where one is congruent to the other in six different ways?

Find ∠B and ∠C, if A is the centre of the circle.

Find the missing angles. As per the convention that we have been following, all line segments marked with a single ‘|’ are equal to each other and those marked with a double ‘|’ are equal to each other, etc.