Understanding Triangle Types

The video explains that all triangles have at least two acute angles, and the third angle determines the type of triangle. An acute triangle has all angles less than 90 degrees, an obtuse triangle has one angle greater than 90 degrees, and a right triangle has one angle exactly 90 degrees.

What is a common feature of all triangles?

• They all have one right angle.

• They all have at least two acute angles.

• They all have one obtuse angle.

• They all have three equal angles.

Which of the following best describes an acute triangle?

• A triangle with one angle exactly 90 degrees.

• A triangle with one angle greater than 90 degrees.

• A triangle with all angles less than 90 degrees.

• A triangle with two angles greater than 90 degrees.

How many angles in an acute triangle measure less than 90 degrees?

• Three

• None

• Two

• One

What distinguishes an obtuse triangle from other types?

• It has one angle exactly 90 degrees.

• It has one angle greater than 90 degrees.

• It has two angles greater than 90 degrees.

• It has all angles less than 90 degrees.

Which type of triangle has one angle measuring exactly 90 degrees?

• Obtuse triangle

• Acute triangle

• Equilateral triangle

• Right triangle