Triangles (Interior & Exterior)

Front

What is a triangle?

Back

A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry.

Front

What are the types of triangles based on sides?

Back

1. Equilateral Triangle: All sides are equal. 2. Isosceles Triangle: Two sides are equal. 3. Scalene Triangle: All sides are different.

Front

What are the types of triangles based on angles?

Back

1. Acute Triangle: All angles are less than 90 degrees. 2. Right Triangle: One angle is exactly 90 degrees. 3. Obtuse Triangle: One angle is greater than 90 degrees.

Front

What is the sum of the interior angles of a triangle?

Back

The sum of the interior angles of a triangle is always 180 degrees.

Front

How do you find the measure of an unknown angle in a triangle?

Back

To find an unknown angle, subtract the sum of the known angles from 180 degrees.

Front

What is an exterior angle of a triangle?

Back

An exterior angle is formed by one side of the triangle and the extension of an adjacent side.

Front

What is the relationship between an exterior angle and the interior angles?

Back

The exterior angle is equal to the sum of the two opposite interior angles.

Front

If one angle of a triangle is 50 degrees and another is 60 degrees, what is the third angle?

Back

The third angle is 70 degrees (180 - 50 - 60 = 70).

Front

What is the formula for the area of a triangle?

Back

Area = 1/2 * base * height.

Front

What is the Pythagorean theorem?

Back

In a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides (a² + b² = c²).