6.8A Triangle Sides and Angles

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 side lengths?

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 Triangle Inequality Theorem?

Back

The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

Can the side lengths 3, 5, and 8 form a triangle?

Back

No, because 3 + 5 is not greater than 8.

Front

In triangle XYZ, if angle X = 83° and angle Y = 68°, what is angle Z?

Back

Angle Z = 180° - (83° + 68°) = 29°.

Front

How do you order the sides of a triangle based on angle measures?

Back

The side opposite the largest angle is the longest, and the side opposite the smallest angle is the shortest.

Front

What is the relationship between angles and sides in a triangle?

Back

In a triangle, larger angles are opposite longer sides, and smaller angles are opposite shorter sides.

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

If a triangle has sides of lengths 15, 12, and 9, does it exist?

Back

Yes, it satisfies the Triangle Inequality Theorem.