Classification of Triangles Based on the Sides

Q.

A triangle having all sides of different lengths is called

1. scalene

2. obtuse

3. equilateral

4. obtuse-angled triangle

Q.

Name a triangle whose one angle is $90°$.

Q. A triangle with sides 5cm , 2cm and 4cm is called a/an triangle.

1. regular
2. scalene
3. equilateral

Q. Identify the type of triangle who sides measure 11 cm, 5 cm and 7 cm.

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

Q.

If two sides of my triangle measure 5 cm, then based on its sides my triangle is ________.

1. Isosceles

2. Scalene

3. Equilateral

4. Acute triangle

Q.
Identify the type of triangle.

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

Q.

If all three sides of a triangle are 4 inches long, then what kind of a triangle is it?

1. Equilateral triangle

2. Right triangle

3. Scalene triangle

4. Isosceles triangle

Q.

If two sides of a $△$ ABC are equal in length and the third side has a different length, then the triangle is a/an:

1. Scalene triangle
   

2. Isosceles triangle
   

3. Right angled triangle
   

4. Equilateral Triangle
   

Q.

Which of the following statements is not correct?

1. The sum of any two sides of a triangle is greater than the third side.

2. A triangle can have all its angles acute.

3. A right-angled triangle cannot be equilateral.

4. The difference between any two sides of a triangle is greater than the third side

Q. Which of the following types of triangles have two equal sides?

(This question can have more than one right answer!)

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

Q.

does a perpendicular bisector divide the triangle symmetrically?

Q. An isosceles traingle has sides of equal length.

1. 2
2. \N
3. 3

Q.

Fill in the blanks with appropriate words and state why

(a) Scale : centimetre :: Protractor : ___
(b) Steps of a ladder : parallel lines :: Red cross : ___
(c) Equilateral triangle : equal sides :: scalene triangle : ___
(d) Pentogon : 5 sides :: Decagon : ___

Q. Burst the bubbles if the sides form a scalene triangle.

1. 5 cm, 5 cm, 8 cm
2. 3 cm, 3 cm, 3 cm
3. 2 cm, 3 cm, 4 cm
4. 7 cm, 3 cm, 7 cm
5. 8 cm, 4 cm, 5 cm
6. 23cm, 13cm, 31cm
7. 10cm, 9cm, 12cm
8. 7cm, 15cm, 20cm
9. 11cm, 11cm, 11cm

Q.

State whether the following is isosceles triangle or not whose measures of sides are given below :

a $cm$, b$cm$, c $cm$

Q. Shapes and Towers
Look for triangles in the pictures below.


• From the activity Changing Shapes can you guess why triangles are used in these towers, bridges etc?
• Look around and find out more places where triangles are used.

Q.

What do we call a triangle with no equal sides?

1. Scalene triangle

2. Equilateral triangle

3. Right triangle

4. Isosceles triangle

Q. Identify the type of triangle.

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