Classification of Triangles

Q.

Question 10
The number of triangles in the given figure is
a) 10
b) 12
c) 13
d) 14

Q. The lengths of the sides of some triangles are given. Say what types of triangles they are.
(1) 3 cm, 4 cm, 5 cm (2) 3.4 cm, 3.4 cm, 5 cm
(3) 4.3 cm, 4.3 cm, 4.3 cm (4) 3.7 cm, 3.4 cm, 4 cm

Q. What type of triangle shown below?

1. Scalene triangle
2. Equilateral triangle
3. Isosceles triangle
4. Right triangle

Q.

Question 4 (d)Try to construct a triangle using matchsticks. Some are shown here.

Can you make a triangle with 6 matchsticks?

(Remember you have to use all the available matchsticks)
Name the type of triangle. If you cannot make a triangle, think of reasons for it.

Q.

Question 4 (c)Try to construct a triangle using matchsticks. Some are shown here.

Can you make a triangle with 5 matchsticks?

(Remember you have to use all the available matchsticks)
Name the type of triangle. If you cannot make a triangle, think of reasons for it.

Q.

Question 4 (a)

Try to construct triangles using match sticks. Some are shown here. Can you make a triangle with:
3 matchsticks?

(Remember you have to use all the available matchsticks)
Name the type of triangle. If you cannot make a triangle, think of reasons for it.

Q.

In the given figure, name the points which lie -

1. in the interior of the triangle ABC
2. in the exterior of triangle ABC
3. on the boundary of the triangle ABC.

Q. James got a wooden square plate and cut it diagonally he observed two triangle. Which type of triangles did he get?

1. Equilateral
2. Obtuse angled
3. Scalene
4. Right angled isosceles

Q.

A line segment that connects a vertex of a triangle to the mid-point of the opposite side is called a ____________ of the triangle.

Q.

Try to construct triangles using match sticks. Some are shown here. Can you make a triangle with

(a) 3 matchsticks?

(b) 4 matchsticks?

(c) 5 matchsticks?

(d)6 matchsticks?

(Remember you have to use all the available matchsticks in each case)

Name the type of triangle in each case. If you cannot make a triangle, think of reasons for it.

Q.

Answer the following:

i. Identify three triangles in the figure.
ii. Write the names of seven angles.
Which two triangles have ∠B as common?

Q. How many edges does a triangular based pyramid have?

1. 7
2. 5
3. 6
4. 8

Q.

Try to construct a triangle using matchsticks. Some are shown here.

Can you make a triangle with 5 matchsticks?

(Remember you have to use all the available matchsticks)
Name the type of triangle. If you cannot make a triangle, think of reasons for it.
[2 marks]

Q. Which of the following triangles have only two equal sides or angles?

1. Isosceles
2. Equilateral
3. Scalene
4. Right

Q. James got a wooden square plate and cut it diagonally he observed two triangle. Which type of triangles did he get?

1. Obtuse angled
2. Equilateral
3. Scalene
4. Right angled isosceles

Q.

Question 4 (b)

Try to construct triangles using matchsticks. Some are shown here. Can you make a triangle with:

4 matchsticks?

(Remember you have to use all the available matchsticks)
Name the type of triangle. If you cannot make a triangle, think of reasons for it.

Q.

Question 7

Draw five triangles and measure their sides. Check in each case, if the sum of the lengths of any two sides is always greater than the third side.

Q. $ABC$ and $BDE$ are two equilateral triangles such that D is the mid-point of BC.

1. 1/4
2. 1/2
3. 1/8
4. 1

Q.

In the figure, $ABC$ is a triangle

vertex opposite to $AC$is$\_\_\_\_$

Q.

In the figure, $ABC$ is a triangle

vertex opposite to $AB$is$\_\_\_\_$

Q.

A triangle has$\_\_\_\_\_\_$medians.