answer key for activity 6

1. ACTIVITY 6 (answer key)
MEASURE MANIA: EXTERIOR OR REMOTE INTERIOR?
Materials Needed: Protractor, Manila Paper, and Ruler.
Procedures:
1. Measure the numbered angles of ∆HEY, ∆DAY, and ∆JOY.
2. Replicate the table in this activity on a piece of manila paper.
3. Indicate the measures on your table and write your answers to
the questions on a piece of manila paper.
1. Compare the measure of exterior ∠1 with either remote interior ∠4 or
∠6 using the relation symbols >, <, or =.
• In ∆HEY, m∠1 is > m∠4.
• In ∆HEY, m∠1 is > m∠6.
• In ∆DAY, m∠1 is = m∠4.
• In ∆DAY, m∠1 is > m∠6.
• In ∆JOY, m∠1 is > m∠4.
• In ∆JOY, m∠1 is > m∠6.

2. 2. Compare the measure of exterior ∠2 with either remote interior ∠5 or
∠6 using the relation symbols >, <, or =.
• In ∆HEY, m∠2 is > m∠5.
• In ∆HEY, m∠2 is > m∠6.
• In ∆DAY, m∠2 is > m∠5.
• In ∆DAY, m∠2 is > m∠6.
• In ∆JOY, m∠2 is < m∠5.
• In ∆JOY, m∠2 is > m∠6.
3. Compare the measure of exterior ∠3 with either remote interior ∠4 or
∠5 using the relation symbols >, <, or =.
• In ∆HEY, m∠3 is > m∠4.
• In ∆HEY, m∠3 is > m∠5.
• In ∆DAY, m∠3 is > m∠4.
• In ∆DAY, m∠3 is > m∠5.
• In ∆JOY, m∠3 is > m∠4.
• In ∆JOY, m∠3 is > m∠5.

3. 4. Making? Conjecture: Your comparison between the measure of an exterior angle of a
triangle and either interior angle in this activity describes the Exterior Angle Inequality
Theorem. With the pattern that you observed, state the exterior angle inequality
theorem.
• The measure of an exterior angle of a triangle is triangle is greater than either of the
non-adjacent interior angles.