Given: AABC DE ||AC Prove: mLA + MLABC + m2c = 180* Statement Reason 1. AABC ; DE || AC 2. 41 and LABE are supplementary 2. Supplement Postulate 1. Given 3. me1+m LABE - 180 3. Definition of supplementary angles 4. m22+ m2a- MLABE 5. m21 + m2 + mL3 - 180° 4. Angie Addition Postulate 5. Substitution Property 7. m1 - mLA; mL3 - mLc 8. mLA + MLABC + mLC = 180° 6. 7 7. Definition of congruency 8. Substitution Property Janet is trying to prove that the sum of the measures of the interior angles of a triangle is 180°. Which reason can she use to justify the statement in line 6? A. ) Alternate interior angles of parallel lines are congruent ) Corresponding angles of parallel lines are congruent В. ) Exterior Angle Theorem C. D. Symmetric Property

Elementary Geometry For College Students, 7e
7th Edition
ISBN:9781337614085
Author:Alexander, Daniel C.; Koeberlein, Geralyn M.
Publisher:Alexander, Daniel C.; Koeberlein, Geralyn M.
ChapterP: Preliminary Concepts
SectionP.CT: Test
Problem 1CT
icon
Related questions
Question
Given: AABC
DE ||AC
Prove: mLA + MLABC + mzC = 180*
Statement
Reason
1. AABC ; DE ||AC
1. Given
2. Supplement Postulate
3. Definition of supplementary angles
4. Angle Addition Postulate
5. Substitution Property
2. 41 and ZABE are supplementary
3. m21+m 2ABE - 180
4. m22 + m23 - MLABE
5. m21 + m22 + m23 - 180°
6. ?
7. Definition of congruency
8. Substitution Property
6. 41 a ZA; 3 a 2C
7. m21 - mLA; mL3 - m2c
8. mLA + MLABC + m2C - 180°
Janet is trying to prove that the sum of the measures of the interior angles of a triangle is 180°.
Which reason can she use to justify the statement in line 6?
A.
Alternate interior angles of parallel lines are congruent
Corresponding angles of parallel lines are congruent
Exterior Angle Theorem
D.
Symmetric Property
B.
C.
Transcribed Image Text:Given: AABC DE ||AC Prove: mLA + MLABC + mzC = 180* Statement Reason 1. AABC ; DE ||AC 1. Given 2. Supplement Postulate 3. Definition of supplementary angles 4. Angle Addition Postulate 5. Substitution Property 2. 41 and ZABE are supplementary 3. m21+m 2ABE - 180 4. m22 + m23 - MLABE 5. m21 + m22 + m23 - 180° 6. ? 7. Definition of congruency 8. Substitution Property 6. 41 a ZA; 3 a 2C 7. m21 - mLA; mL3 - m2c 8. mLA + MLABC + m2C - 180° Janet is trying to prove that the sum of the measures of the interior angles of a triangle is 180°. Which reason can she use to justify the statement in line 6? A. Alternate interior angles of parallel lines are congruent Corresponding angles of parallel lines are congruent Exterior Angle Theorem D. Symmetric Property B. C.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Half-angle, Double-angle, and Product-Sum Formulae
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, geometry and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Elementary Geometry For College Students, 7e
Elementary Geometry For College Students, 7e
Geometry
ISBN:
9781337614085
Author:
Alexander, Daniel C.; Koeberlein, Geralyn M.
Publisher:
Cengage,
Elementary Geometry for College Students
Elementary Geometry for College Students
Geometry
ISBN:
9781285195698
Author:
Daniel C. Alexander, Geralyn M. Koeberlein
Publisher:
Cengage Learning