Angles in a Transversal

Angle 1 is also 18 degrees because corresponding angles are congruent.

If angle 2 is 18 degrees, what is the measurement of angle 1? How do you know?

45 deg: 2, 3, 6, 7 135 deg: 1, 4, 5, 8

If angle 6 is 45 degrees, what are the measures of all of the other angles?

110 degrees

If angle 8 is 110 degrees, what is the measurement of angle 1?

Angle 1 and angle 5 are supplementary. 180-80- 100 degrees.

If the measure of angle 1 is 80 degrees, what is the measurement of angle 5? How do you know?

Angle 7 = 115 degrees. Explanation 1: Angle 2 and angle 7 are alternate interior angles, so the measurements are equivalent Explanation 2: Angle 2 and angle 5 are vertical angles, which means angle 5 is also 115 degrees. Angle 5 and angle 7 are corresponding angles, so they are equivalent.

If the measure of angle 2 is 115 degrees, what is the measurement of angle 7? How do you know? Give two different explanations.

Angle 6 is 30 degrees. Angle 6 and angle 7 are vertical angles, so they are equivalent. Also, Angle 7 and angle 5 are supplementary, so angle 5 is 180-30 = 150 degrees. Angle 5 and 6 are supplementary, so if angle 5 is 150 degrees, then angle 6 is 30 degrees.

If the measure of angle 7 is 30 degrees, what is the measurement of angle 6? How do you know? Give two different explanations.

Alternate interior angles

What is the relationship between angle 1 and angle 2?

Vertical angles

What is the relationship between angle 1 and angle 4?

Corresponding angles

What is the relationship between angle 2 and angle 6?

Corresponding angles

What is the relationship between angle 4 and angle 8?

Vertical angles

What is the relationship between angle 5 and angle 8?

Corresponding angles

What is the relationship between angle 7 and angle 5?

Alternate interior angles

What is the relationship between angles 5 and 6?

Angle 4, 5, 8

Which other angles are congruent to angle 1?