Which of the following is not true for an exterior angle of a regular polygon with n sides?

1

(a)

Each exterior angle = \(\frac { { 360 }^{ 0 } }{ n } \)

(b)

Exterior angle = 180° - Interior angle

(c)

n = \(\frac { { 360 }^{ 0 } }{ Exterior\quad angle } \).

(d)

Each exterior angle = \(\frac { (n-2)\times 180^{ 0 } }{ n } \)

If the sum of the interior angles of a polygon is 18 right angles, then the number of sides is

1

(a)

9

(b)

10

(c)

11

(d)

12

ABCD is a quadrilateral, in which AB = 5 cm, CD = 8 cm and the sum of angles A and D is 180°. What is the name of this quadrilateral?

1

(a)

Parallelogram

(b)

Trapezium

(c)

Rhombus

(d)

Cannot be determined

Prisha has a farm land, which is triangular shape. What is the sum of all the exterior angles taken in an order of the farm land?

1

(a)

90°

(b)

180°

(c)

360°

(d)

Cannot be determined

For which of the following quadrilaterals, diagonals are perpendicular to each other?

1

(a)

Parallelogram

(b)

Trapezium

(c)

Rectangle

(d)

Kite

_______ is a regular quadrilateral.

1

(a)

Square

The name of three-sided regular polygon is _______

1

(a)

An equilateral triangle

If the diagonals of a quadrilateral bisect each other, it is a ______

1

(a)

Parallelogram

If one diagonal of a rectangle is 8 cm long, length of the other diagonal is _______

1

(a)

8 cm

The adjacent angles of a parallelogram are _______

1

(a)

Supplementary

All trapeziums are kites.

1

(a) True

(b) False

Diagonals of rectangle intersects at right angle.

1

(a) True

(b) False

Diagonals of rhombus intersects at right angle.

1

(a) False

(b) True

In trapezium, two sides are parallel.

1

(a) False

(b) True

In a kite, two pair of consecutive sides are equal.

1

(a) False

(b) True

Find the number of diagonals possible in regular hexagon.

2

(a)

Find the measure of each interior angle of a regular polygon with 12 sides.

2

(a)

Find the measure of each interior angle of a regular polygon with 18 sides.

2

(a)

What is the sum of the measures of the angles of a convex quadrilateral? Will this property hold, if the quadrilateral is not convex? (Make a non-convex quadrilateral and try!)

2

(a)

Find the sum of interior angles of a regular polygon having 11 sides.

2

(a)

Examine the table. (Each figure is divided into triangles and the sum of the angles deduced from that).

Figure
Side	3	4	5	6
Angle sum	1800	2 x 1800-(4-2) x 1800	3 x 1800=(5-2) x 1800	4 x 1800=(6-2) x 1800

What can you say about the angle sum of a convex polygon with number of sides?
(a) 7 (b) 8 (c) 10 (d) n

3

(a)

Find x + y + z

3

(a)

Find x, in the following figures.

3

(a)

The measures of two adjacent angles of a parallelogram are in the ratio 3 : 2. Find the measureof each of the angles of the parallelogram.

3

(a)

Two adjacent angles of a parallelogram have equal measure. Find the measure of each of the angles of the parallelogram.

3

(a)

Given here are some figures.

Classify each of them on the basis of the following.
(a) Simple curve
(b) Simple closed curve
(c) Polygon
(d) Convex polygon
(e) Concave polygon

5

(a)

Take a regular hexagon, in the given figure
(a) What is the sum of the measures of its exterior angles x, y, z, p, q and r?
(b) Is X = Y = z = p = q = r? Why?
(c) What is the measure of each?
(i) exterior angle
(ii) interior angle
(d) Repeat this activity for the cases of
(i) a regular octagon
(ii) a regular 20-gon

5

(a)