Q.1. Fill in the blanks using the correct word given in brackets:
(i) All circles are _______(congruent, similar)
(ii) All squares are _______ (similar, congruent)
(iii) All _______ triangles are similar. (isosceles, equilateral)
(iv)Two polygons of the same number of sides are similar, if
(a) their corresponding angles are _______ and
(b) their corresponding sides are _______ (equal, proportional).
Sol. (i) All circles are similar.
(ii) All squares are similar.
(iii) All equilateral triangles are similar.
(iv) Two polygons of the same number of sides are similar if:
(a) Their corresponding angles are equal and
(b) Their corresponding sides are proportional.
Q.2. Give two different examples of pair of:
(i) similar figures
(ii) non-similar figures.
Sol. (i) (a) Any two circles are similar figures.
(b) Any two squares are similar figures.
(ii) (a) A circle and a triangle are non-similar figures.
(b) An isosceles triangle and a scalene triangle are non-similar figures.
Q.3. State whether the following quadrilaterals are similar or not:
Sol. No, the sides of quadrilateral PQRS and ABCD are proportional but their corresponding angles are not equal.
∴ These are not similar