Page 53 - Mathematics Class - X

Viva-Voce

1. ‘Any two congruent figures are similar’. Justify the statement.
Ans. Two congruent figures are similar to each other. For example, two congruent squares have their sides equal,
i.e. proportional to each other as well as all the corresponding angles are equal to each other.
2. ‘Any two similar figures are not congruent’. Justify the statement.

Ans. In similar figures, their corresponding angles are equal while their corresponding sides are proportional, not
equal to each other. So, two similar figures are not necessarily congruent to each other.
3. ‘Two triangles are similar, if their corresponding angles are equal’. Is this statement true? Give reason for
your answer.
Ans. Two triangles are similar, if either their corresponding angles are equal or corresponding sides are
proportional. So, the given statement is true.

4. Give two examples of pair of similar figures.
Ans. (i) Any two equilateral triangles.

(ii) Any two regular pentagons.
5. ‘Any two squares are congruent.’ Is this statement correct? If not, then rewrite it.
Ans. Any two squares are congruent, is not a correct statement. It can be rewritten as ‘Any two squares
are similar’.

MCQs

1. What is the other name of Basic Proportionality Theorem?
a) Triangle theorem b) Base Triangle theorem

c) Thales theorem d) none of these
2. Which of the following is the criterion for similarity of two triangles?

a) AAA criterion b) SSS criterion c) SAS criterion d) All of these
3. Any two rectangles are
a) Similar b) Congruent c) both (a) and (b) d) None of these

4. Are square and rectangle similar?
a) Yes b) No c) In some cases d) None of these

5. Which figures have the same shape but not necessarily the same size?
a) Similar figures b) Congruent figures c) Both (a) and (b) d) None of these

Answers: 1. c) Thales theorem 2. d) All of these 3. a) Similar

4. b) No 5. a) Similar figures

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