Classifying Triangles by Sides and Angles

The video tutorial explains the classification of triangles based on the lengths of their sides and the measures of their angles. It covers scalene, equilateral, and isosceles triangles, as well as obtuse, right, and acute triangles. The tutorial also discusses how to name triangles by their angles and sides and provides a method for calculating missing angles in triangles, emphasizing that the sum of angles in a triangle is always 180 degrees.

What type of triangle has all sides of different lengths?

• Acute

• Scalene

• Isosceles

• Equilateral

Tags

CCSS.4.G.A.2

What do we call a triangle with all sides equal?

• Scalene

• Equilateral

• Obtuse

• Isosceles

Tags

CCSS.4.G.A.2

Which triangle has two equal sides?

• Right

• Isosceles

• Scalene

• Equilateral

Tags

CCSS.4.G.A.2

What type of triangle has one angle greater than 90 degrees?

• Acute

• Right

• Obtuse

• Equilateral

Tags

CCSS.4.G.A.2

What is a right triangle?

• A triangle with all sides equal

• A triangle with one angle greater than 90 degrees

• A triangle with one angle exactly 90 degrees

• A triangle with all angles less than 90 degrees

Tags

CCSS.4.G.A.2

Which triangle always has angles measuring 60 degrees?

• Scalene

• Isosceles

• Obtuse

• Equilateral

Tags

CCSS.4.G.A.2

How many degrees do the angles of any triangle sum up to?

• 360 degrees

• 90 degrees

• 180 degrees

• 270 degrees

Tags

CCSS.8.G.A.5

If two angles in a triangle are 70 and 30 degrees, what is the measure of the third angle?

• 60 degrees

• 80 degrees

• 90 degrees

• 70 degrees

Tags

CCSS.8.G.A.5

What type of triangle is formed when two angles are known, and the third is calculated?

• Scalene

• Isosceles

• Equilateral

• Cannot be determined

Tags

CCSS.4.G.A.2

In an isosceles triangle, if two angles are given as 70 and 30 degrees, what is incorrect about the third angle being 80 degrees?

• The triangle should be equilateral

• The triangle is not drawn to scale

• The calculation is incorrect

• Isosceles triangles cannot have such angles

Tags

CCSS.8.G.A.5