Understanding Opposite Angles by the Vertex

The video tutorial by Gigi explains the concept of opposite angles by vertex, known as OPV. It covers the properties of these angles, demonstrating that they are congruent. The tutorial includes multiple example problems to illustrate how to solve for unknown angles using the properties of opposite angles. Gigi also provides a demonstration to prove the congruence of opposite angles and discusses the concept of supplementary angles. The video concludes with a summary of the key points and encourages viewers to explore further lessons on angles.

What is formed when two lines intersect at a point?

• Five angles

• Four angles

• Two angles

• Three angles

What are angles called when they are opposite each other at the vertex?

• Complementary angles

• Supplementary angles

• Congruent angles

• Adjacent angles

Which property do opposite angles by the vertex share?

• They are supplementary

• They are always obtuse

• They are always acute

• They are congruent

If two angles are opposite by the vertex and one measures 30 degrees, what is the measure of the other angle?

• 30 degrees

• 120 degrees

• 60 degrees

• 90 degrees

What is the measure of an obtuse angle?

• More than 180 degrees

• More than 90 degrees but less than 180 degrees

• Exactly 90 degrees

• Less than 90 degrees

How do you find the measure of an angle if you know its opposite angle by the vertex?

• Double the measure

• Use the same measure

• Subtract from 180 degrees

• Add 90 degrees

What is the sum of angles that are supplementary?

• 180 degrees

• 270 degrees

• 360 degrees

• 90 degrees

If angle A is 37 degrees and is opposite to angle B by the vertex, what is the measure of angle B?

• 53 degrees

• 180 degrees

• 37 degrees

• 143 degrees

What is the relationship between angles that are opposite by the vertex?

• They are complementary

• They are different

• They are supplementary

• They are equal

Which of the following is true about angles that are opposite by the vertex?

• They are always right angles

• They are always acute

• They are always equal

• They are always obtuse