In this video, Mr. Jay explains what an acute triangle is, emphasizing that all angles in an acute triangle are less than 90 degrees. He discusses how triangles can be classified by their angles and provides two examples: one with specific angle measurements and another with an equilateral triangle. The video concludes with a recap of the key points about acute triangles.

What is the defining characteristic of an acute triangle?

• All angles are more than 90 degrees

• All angles are less than 90 degrees

• All angles are less than 180 degrees

• All angles are exactly 90 degrees

Tags

CCSS.4.G.A.2

What type of triangle is formed when all angles are less than 90 degrees?

• Equilateral triangle

• Right triangle

• Obtuse triangle

• Acute triangle

Tags

CCSS.4.G.A.2

How can triangles be classified?

• By angle or side properties

• By size

• By color

• By area

Tags

CCSS.4.G.A.2

How are acute triangles classified?

• By their perimeter

• By their area

• By their sides

• By their angles

Tags

CCSS.4.G.A.2

What are the angle measures in the first example of an acute triangle?

• 100 degrees, 40 degrees, 40 degrees

• 60 degrees, 60 degrees, 60 degrees

• 90 degrees, 45 degrees, 45 degrees

• 85 degrees, 30 degrees, 65 degrees

Tags

CCSS.4.G.A.2

What does a mark in each angle of a triangle signify?

• All angles are obtuse

• All angles are right angles

• All angles are equal

• All angles are complementary

Tags

CCSS.8.G.A.5

What is the sum of all angles in any triangle?

• 270 degrees

• 180 degrees

• 360 degrees

• 90 degrees

Tags

CCSS.8.G.A.5

If a triangle has three equal angles, what is the measure of each angle?

• 60 degrees

• 45 degrees

• 30 degrees

• 90 degrees

Tags

CCSS.8.G.A.5

What is the angle measure of each angle in an equilateral triangle?

• 45 degrees

• 60 degrees

• 75 degrees

• 90 degrees

Tags

CCSS.8.G.A.5

What can be concluded about a triangle if all angles are acute?

• It is always an isosceles triangle

• It is always a right triangle

• It is always an acute triangle

• It is always an equilateral triangle

Tags

CCSS.4.G.A.2