Isosceles Equilateral and Scalene Triangle Worksheet

Triangles can be classified into different categories based on the length of their sides or the measurement of their angles. In this worksheet, we will explore the different types of triangles and how to classify them.

Example 1:

Find the perimeter of a triangle when its sides are 3.5 cm, 3.5 cm, and 4.5 cm.

The perimeter of the triangle is the sum of all three sides, which is 3.5 + 3.5 + 4.5 = 11.5 cm.

Example 2:

Is it possible to have a triangle with angles of 50°, 50°, and 90°? Give reason in support of your answer.

Yes, it is possible to have a triangle with these angles because the sum of all three angles must equal 180°. The two 50° angles can be adjacent to each other, forming an isosceles triangle, and the third angle can be 90°.

Classifying Triangles

Triangles can be classified based on their sides or angles. If none of the sides are equal in length, it is called a scalene triangle. If a triangle has two equal sides, it is referred to as an isosceles triangle. In an equilateral triangle, all three sides have equal lengths.

Types of Triangles

* Scalene Triangle: A triangle with all three sides of different measurements.

* Isosceles Triangle: A triangle with two sides of equal measurement.

* Equilateral Triangle: A triangle with all three sides of the same measurement.

* Right Triangle: A triangle with at least one angle of 90 degrees.

* Obtuse Triangle: A triangle with an angle that measures more than 90 degrees but less than 180 degrees.

* Acute Triangle: A triangle with all angles measuring less than 90 degrees.

In conclusion, triangles can be classified into different categories based on their sides or angles. Understanding the different types of triangles and how to classify them is important in geometry and mathematics. By recognizing the characteristics of each type of triangle, we can better understand the properties and relationships between shapes.

Worksheet Questions:

1. Find the perimeter of a triangle when its sides are 10 cm, 12 cm, and 2 cm.

2. Is it possible to have a triangle with angles of 30°, 60°, and 90°? Give reason in support of your answer.

3. Classify the following triangles as scalene, isosceles, or equilateral: (a) 5 cm, 5 cm, 6 cm; (b) 8 cm, 8 cm, 10 cm.

Answer

1. The perimeter of the triangle is 24 cm.

2. Yes, it is possible to have a triangle with these angles because the sum of all three angles must equal 180°.

3. (a) Scalene; (b) Isosceles

Isosceles equilateral and scalene triangle worksheet