Download GEOMETRY NVESTIGATION Corresponding and Alternate Angles

GEOMETRY
NVESTIGATION
Corresponding and Alternate Angles
Objective: In this investigation you will learn about corresponding angles and alternate angles.
PART 1 : Corresponding Angles
Step 1: In the space below are two parallel lines. (Trust me on this one.) Draw a transversal through the
parallel lines.
Step 2: Label the eight angles created “1” through “8”
Step 3: There are four pairs of corresponding angles. Label them in the chart below:
Angle ______ corresponds to angle _____.
Angle ______ corresponds to angle _____.
Angle ______ corresponds to angle _____.
Angle ______ corresponds to angle _____.
Step 4: Choose one pair of corresponding angles to work with.
What pair are you using? <
and <
Measure each angle with a protractor. Write their measurements here:
What do you notice?
Step 5: Repeat Step 4 with your next pair of corresponding angles.
Step 6: Write your conjecture about the measures of corresponding angles below.
Conjecture: If two parallel lines are cut by a transversal, then the measures of
corresponding angles are _________________________________.
PART 2: Alternate Interior Angles
Step 1: Using the parallel lines and the numbered angles on the front side. Answer the following
Angle ______ is an alternate interior angle with angle _________.
Angle ______ is an alternate interior angle with angle _________.
Step 2: Measure the first pair of alternate interior angles. What do you notice about the measurement:
Step 3: Repeat Step 2, and write a conjecture below:
CONJECTURE: If you have two parallel lines cut by a transversal, then the
measures of alternate interior angles are _________________________.
Part 3: Alternate Exterior Angles
Step 1: Using the parallel lines and the numbered angles on the front side. Label the two pairs of alternate
exterior angles.
Angle ______ is an alternate exterior angle with angle _________.
Angle ______ is an alternate exterior angle with angle _________.
Step 2: Measure the first pair of alternate exterior angles. What do you notice about the measurement:
Step 3: Repeat Step 2, and write a conjecture below:
CONJECTURE: If you have two parallel lines cut by a transversal, then the
measures of alternate exterior angles are _________________________.