Parallel Lines Intersected by a Transversal
a and b are parallel lines. They are cut by transversal c. Drag the blue points on c to move the transversal. [br][br]Note: Do not allow the blue points to fall inside the parallel lines or the angles will disappear!
Identify a pair of Corresponding Angles.
What is the relationship between the angle measures?
Move one of the blue dots to a new point and identify another pair of corresponding angles.
What is the relationship between the angle measures?
What conclusion can you make about the angle measurement relationship between corresponding angles?
Identify a pair of Alternate-Interior Angles
What is the relationship between the angle measures?
Move one of the blue dots to a new point and identify a different pair of Alternate Interior Angles.
What is the relationship between the angle measures?
What can you conclude about the angle measurement relationship for Alternate Interior Angles?
Identify a pair of Same-Side Interior Angles.
What is the relationship between the angle measures?
Move one of the blue dots to a new position. Identify another pair of Same-Side Interior Angles.
What is the angle measurement relationship?
Identify a pair of Alternate-Exterior angles.
What is the relationship between the angle measures?
Move one of the blue dots to a new position. Identify another pair of Alternate-Exterior Angles.
What is the relationship between the angle measures?
What can you conclude about the angle measurement relationship between Alternate-Exterior Angles?
Create a set of parallel lines. Create a transversal line that cuts through them.
Identify a pair of Corresponding Angles.
Use the measurement tool to determine their angle measures. Did your conclusion from the previous activity hold true?
Identify a pair of Alternate-Interior Angles.
Use the measurement tool to determine their angle measures. Did your conclusion from the previous activity hold true?
Identify a pair of Same-Side Interior Angles.
Use the measurement tool to determine their angle measures. Did your conclusion from the previous activity hold true?
Identify a pair of Alternate-Exterior Angles
Use the measurement tool to determine their angle measures. Did your conclusion from the previous activity hold true?
In your own words, describe the angles formed by parallel lines and transversals. Give examples to support your answer.
A store owner uses pieces of tape to paint a window advertisement. The letters are slanted at an 80 degree angle.
Use the the picture above to answer the following questions.
What is the measure of <1?
=
Use the image above to analyze the error.
Describe and correct the error in describing the angle relationship.
Two horizontal lines are cut by a transversal. What is the least number of angle measures you need to know in order to find the measure of every angle? Explain your reasoning.