Triangle Angles and Classifications

This video tutorial covers Chapter 10.3 on triangles, focusing on the properties of triangle angles, solving for unknown angles using algebra, and understanding angle ratios. It also explains the classification of angles and triangles by their measures and sides, including acute, right, obtuse, scalene, isosceles, and equilateral triangles. The video emphasizes the importance of understanding these concepts for solving geometry problems.

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

• 360 degrees

• 270 degrees

• 180 degrees

• 90 degrees

If two angles of a triangle are 89 degrees and 54 degrees, what is the measure of the third angle?

• 37 degrees

• 47 degrees

• 39 degrees

• 45 degrees

In a triangle with angles in the ratio 1:3:8, what is the measure of the smallest angle?

• 60 degrees

• 45 degrees

• 30 degrees

• 15 degrees

What is the measure of the largest angle in a triangle with angles in the ratio 1:3:8?

• 90 degrees

• 120 degrees

• 135 degrees

• 150 degrees

Which type of angle is exactly 90 degrees?

• Acute

• Right

• Obtuse

• Straight

An angle that is greater than 90 degrees but less than 180 degrees is called what?

• Acute

• Right

• Obtuse

• Straight

What type of triangle has all angles less than 90 degrees?

• Obtuse triangle

• Acute triangle

• Scalene triangle

• Right triangle

Which triangle has no congruent sides?

• Isosceles

• Equilateral

• Scalene

• Right

A triangle with one right angle and all sides of different lengths is classified as what?

• Obtuse scalene

• Acute scalene

• Right scalene

• Right isosceles

If a triangle has two sides of equal length and all angles less than 90 degrees, how is it classified?

• Equilateral

• Right isosceles

• Obtuse isosceles

• Acute isosceles