Angles and Triangle Properties

The video tutorial by Mr. Cell covers the angle sum theorem for triangles, explaining that the sum of interior angles in a triangle is always 180 degrees. It defines interior angles, discusses problem-solving strategies, and demonstrates how to name angles using vertices. The tutorial also explores corresponding and alternate interior angles in parallel lines, provides proofs and angle relationships, and offers methods for calculating unknown angles. The session concludes with a review and practice problems to reinforce the concepts learned.

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

• 360 degrees

• 270 degrees

• 90 degrees

• 180 degrees

When naming an angle in a triangle, how many letters should be used?

• One

• Three

• Two

• Four

What is the correct way to name the angle at vertex B in triangle ABC?

• Angle B

• Angle ABC

• Angle BAC

• Angle CAB

What are corresponding angles?

• Angles that are supplementary

• Angles that are equal and on the same side of the transversal

• Angles that are equal and on opposite sides of the transversal

• Angles that are complementary

Which angles are equal when two parallel lines are cut by a transversal?

• Supplementary angles

• Vertical angles

• Adjacent angles

• Alternate interior angles

In a proof involving parallel lines, what is the sum of the angles on a straight line?

• 270 degrees

• 360 degrees

• 180 degrees

• 90 degrees

What is the measure of a straight angle?

• 360 degrees

• 270 degrees

• 180 degrees

• 90 degrees

If two angles in a triangle are 45 degrees and 45 degrees, what is the measure of the third angle?

• 60 degrees

• 180 degrees

• 90 degrees

• 45 degrees

How do you find the measure of an unknown angle in a triangle if the other two angles are known?

• Add the two known angles and subtract from 180

• Multiply the two known angles

• Add the two known angles and subtract from 360

• Divide the sum of the two known angles by 2

What is the measure of angle EFD if the other two angles in the triangle are 101 degrees and 40 degrees?

• 39 degrees

• 49 degrees

• 59 degrees

• 69 degrees