ICSE Board: Suggested Books ICSE Board: Foundation Mathematics Class 8: Reference Books Class 8: NTSE Preparation --------------------------------------------------------------

Q.1 In the adjourning figure, name:

- The point are
- Five line segments are
- Four Rays are
- Four lines are
- Four Collinear points are

Q.2 In the adjoining figure, name :

- Two points of intersecting lines are
- intersecting at R
- intersecting at Q.

- Three concurrent lines and their point of concurrence.
- and point of concurrence is R

- Three rays are, some other rays are , etc.
- Two line segments are

Q.3 State whether the following statements are true or false :

- A ray has no end Point:
- A line AB is the same as line BA:
- A ray AB is the same as BA:
- A line has a definite length:
- Two planes always meet in a line:
- A plane has length and breadth but no thickness:
- Two distinct points always determine a unique line:
- Two lines may intersect in two points:
- Two intersecting lines cannot be both parallel to the same line:

Q.4 Two adjacent angles on a straight line are Find (i) the value of ii) the measure of each angle

Q.5. Two adjacent angles on a straight line are – Find :(i) the value of ii) the measure of each angle

ii) The measure of angles

Q.6 Two adjacent angles on a straight line are in the ratio 3. Find the measure of each angle:

i) The ratio of angles

ii) Therefore the angles are and

The two angles are

Q.7 In the adjoining figure, AOB is a straight line. Find the value . Hence ,find,

Therefore

And

Q.8 In the adjoining figure, AOB is a straight line. If , find the values of .

Therefore

Or

Q.9 In the adjoining figure, what value of make AOB a straight line?

For to be a straight line

Q 10. In the adjoining figure, find the value of .

Q 11. In each of the following figures, two lines intersect at a point . Find the value of

(vertically opposite angle)

Or

We could have also used

(vertically Opposite angles)

(Angles on a straight line are supplementary)

(Vertically opposite angles)

(Vertically opposite angles)

(Angles on a straight line)

(Vertically opposite angles)

(Vertically opposite angles)

(Vertically opposite angles)

Substituting (ii) in (i)

Q.12 Prove that the bisectors of two adjacent supplementary angles include a right angle.

Let

Bisector of

Bisector of

Therefore

Hence

Q.13 Find the measure of an angle which is (i) equal to its complement (ii) equal to its supplement.

i) If the

If

ii) If the

Q.14 Find the angle which is more than its complement.

Let the angle

Complement

Given

or

Q.15 Find the angle which is less than its complement.

Let the angle

Complement

Given

Q.16 Find the angle which is more than its supplement.

Let the angle

Supplement

Given

Or

Q.17 Find the angle which is less than its supplement.

Let the angle

Supplement

Given,

Q.18 Find the angle which is four times its complement.

Let the angle

Complement

Given

Q.19 Find the angle which is five times its supplement.

Let the angle

Complement

Given

Or

Q.20 Find the angle whose supplement is four times its complement.

Let the angle

Complement

Supplement

Given,

Q.21 Find the angle whose complement is one third of its supplement.

Let the angle

Complement

Supplement

Given

Q.22 Two complementary angles are in the ratio Find the angles.

Let the angle

Complement

Given

or

The complement

Hence the angles are

Q.23 Two supplementary angles are in the ratio 7. Find the angles.

Let the angle

Supplement

Given

Hence the angles are

Q.24 Find the measure of an angle, if seven times its complement is less than three times its supplement.

Let the angle

Complement

Supplement

Given

ICSE Board: Suggested Books ICSE Board: Foundation Mathematics Class 8: Reference Books Class 8: NTSE Preparation --------------------------------------------------------------