Page 59 - Mathematics Class - IX

Viva-Voce

1. What are the important features of a parallelogram?
Ans. 1. Opposite sides are equal and parallel. 3. Opposite angles are equal.
2. Diagonals bisect each other.
2. How can we find the area of a parallelogram with the help of a triangle (assume both have same base)?

Ans. Area of parallelogram = 2 × Area of a triangle
3. Name the type of parallelogram if its all the four sides are equal.
Ans. Rhombus
4. If a triangle and a parallelogram are on the same base and between the same parallels, then how can we
relate the area of a triangle and a parallelogram?
Ans. Area of the triangle is half the area of parallelogram.

5. How can we find the altitude of a parallelogram?
Ans. Altitude of a parallelogram is the perpendicular drawn from one line to the another parallel line.
6. A parallelogram whose one of the angles is a right angle then what is the shape formed?

Ans. Rectangle
7. If the angles of a triangle are in the ratio of 4:5:9 then what is the shape of this triangle?
Ans. A right-angled triangle

MCQs

1. If the area of || gm PQRS = 25 cm and area of ∆PQR = x, then value of x is
2
a) 25 cm b) 12.5 cm c) 12.5 cm d) 25 cm
2
2
2. In a triangle, base and height are 3 cm and 4 cm respectively. What is the area of triangle?
a) 4 cm b) 5 cm c) 6 cm d) 13 cm 2
2
2
2
3. The area of a rhombus is 10 cm . If one of its diagonal is 4 cm, then the other diagonal is
2
a) 5 cm b) 2.5 cm c) 6 cm d) 8 cm
4. Area of a trapezium is given by
1
a) b × h b) × b × h
2
1
c) (sum of bases) × height d) None of these
2
5. ABCD is a || gm and AC is the diagonal. Find ar (∆ABC) : ar (∆ACD).

a) 2 : 1 b) 1 : 2 c) 1 : 3 d) 1 : 1

Answers: 1. b) 12.5 cm 2. c) 6 cm 3. a) 5 cm
2
2
1
4. c) (sum of bases) × height 5. d) 1 : 1
2
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