Types and Properties of Triangles

The video tutorial introduces triangles, explaining their basic properties and classifications. It covers types of triangles based on sides: equilateral, isosceles, and scalene, and types based on angles: acute, obtuse, and right-angled. The tutorial also includes examples to help identify triangles by their sides and angles, reinforcing the learning objectives.

What is a triangle?

• A circle

• A shape with two sides

• A simple closed figure with three line segments

• A four-sided polygon

Which of the following is true for an equilateral triangle?

• It has a right angle

• All sides are equal

• Two sides are equal

• All sides are different

In an isosceles triangle, how many sides are equal?

• One side

• No sides

• At least two sides

• All three sides

What defines a scalene triangle?

• It has a right angle

• All sides are different

• Two sides are equal

• All sides are equal

What is an acute angled triangle?

• A triangle with one right angle

• A triangle with all angles less than 90 degrees

• A triangle with all sides equal

• A triangle with one angle more than 90 degrees

Which triangle has one angle greater than 90 degrees?

• Right angled triangle

• Obtuse angled triangle

• Equilateral triangle

• Acute angled triangle

What is a right angled triangle?

• A triangle with one angle more than 90 degrees

• A triangle with all angles less than 90 degrees

• A triangle with one angle equal to 90 degrees

• A triangle with all sides equal

In triangle MNO, if angle N is obtuse and two sides are equal, what type of triangle is it?

• Right angled scalene triangle

• Obtuse angled isosceles triangle

• Acute angled equilateral triangle

• Equilateral triangle

If a triangle has all angles measuring 60 degrees, what type of triangle is it?

• Scalene triangle

• Acute angled equilateral triangle

• Obtuse angled triangle

• Right angled triangle

What should you remember about triangles?

• They can only be equilateral

• They have four sides

• They can be classified by sides and angles

• They are always right angled