Question

Choose the best answer:
1. If three angles of a quadrilateral are each equal to 75°, the fourth angle is
(a) 150° (b) 135° (c) 45° (d) 75°
2. For which of the following, diagonals bisect each other?
(a) Square (b) Kite (c) Trapezium (d) Quadrilateral
3. For which of the following figures, all angles are equal?
(a) Rectangle (b) Kite (c) Trapezium (d) Rhombus
4. For which of the following figures, diagonals are perpendicular to each other?
(a) Parallelogram (b) Kite (c) Trapezium (d) Rectangle
5. For which of the following figures, diagonals are equal?
(a) Trapezium (b) Rhombus
(c) Parallelogram (d) Rectangle
6. Which of the following properties describe a trapezium?
(a) A pair of opposite sides is parallel
(b) The diagonals bisect each other.
(c) The diagonals are perpendicular to each other.
(d) The diagonals are equal.
7. Which of the following is a property of a parallelogram?
(a) Opposite sides are parallel.
(b) The diagonals bisect each other at right angles.
(c) The diagonals are perpendicular to each other.
(d) All angles are equal.
8. What is the maximum number of obtuse angles that a quadrilateral can have ?
(a) 1 (b) 2 (c) 3 (d) 4
9. How many non-overlapping triangles can we make in an-gon (polygon having n sides), by joining the vertices?
(a) n –1 (b) n –2 (c) n –3 (d) n –4
10. What is the sum of all the angles of a pentagon?
(a) 180° (b) 360° (c) 540° (d) 720°
11. What is the sum of all angles of a hexagon?
(a) 180° (b) 360° (c) 540° (d) 720°
12. If two adjacent angles of a parallelogram are (5x – 5)° and
(10x + 35)°, then the ratio of these angles is
(a) 1 : 3 (b) 2 : 3 (c) 1 : 4 (d) 1 : 2
13. A quadrilateral whose all sides are equal, opposite angles are equal and the diagonals bisect each other at right angles is a __________.
(a) rhombus (b) parallelogram (c) square (d) rectangle
14. A quadrilateral whose opposite sides and all the angles are equal is a
(a) rectangle (b) parallelogram (c) square (d) rhombus
15. A quadrilateral whose all sides, diagonals and angles are equal is a
(a) square (b) trapezium
(c) rectangle (d) rhombus​

Answer 1

1.75+75+75= 225 =360-225 = 135

2. D Quadrilaterl

3.A .Rectangle

4.Rhombus

5.The diagonals of quadrilateral are equal if angles are equal..Hence answer is D.Rectangle

6.B diagonals bisect each other

7.A.opp sides are parallel

8. B.2

9. n - 2

10. c.540

11. d 720

12.A 1: 3

We know that adjacent angles of a parallelogram sums to 180°. So, ( 5x - 5 )° + ( 10x + 35 )° = 180° => 5x° - 5° + 10x° + 35° = 180° => 15x° + 30° = 180° => 15x° = 180° - 30° => x = 150/15 = 10 Hence, Adjacent angles are ( 5x - 5 )° and ( 10x + 35 )° => ( 5 * 10 - 5 )° and ( 10 * 10 + 35 )° => ( 50 - 5 )° and ( 100 + 35 )° => 45° and 135° Now, The required ratio = 45° / 135° = 9 / 27 = 3 / 9 = 1 / 3 = 1 : 3

13. A Rhombus

14.C Rectangle

15. Square