## julie001 3 years ago NEED HELP FOR PROOFS! fill in missing step

1. julie001

2. ash2326

(10.03 HC) Look at the figure shown below. A student made the table shown below to prove that XY is equal to YZ. Sample Response Statements Justifications 1. NY = MY Given 2. m∡MYX = m∡NYZ Given 3. m∡XNY = m∡ZMY Given 4. 5. m∡MYZ = m∡MYX + m∡XYZ Angle Addition Postulate 6. m∡MYZ = m∡NYZ + m∡XYZ Substitution 7. m∡NYX = m∡MYZ Transitive Property 8. XYN ≅ ZYM ASA postulate 9. XY = ZY CPCTC A. Provide the missing statement and justification in the proof. B. Using complete sentences, explain why the proof would not work without the missing step.

3. julie001

yea thats the problem

4. julie001

can u guys help?

5. ash2326

@julie001 always post the question, don't upload a docx file. Everyone doesn't have Microsoft word. Thanks Here's the picture

6. julie001

oh ok

7. ash2326

8. julie001

9. julie001

i just need to know the step missing

10. ash2326

Yeah, but I'm confused, what could be missing!!

11. julie001

lol thats wat im saying

12. ash2326

@Zarkon do you have any ideas?

13. julie001

arite thanks anyways i'll just guess

14. ash2326

Nope, wait. We'll fill in the missing step

15. zepp

There's something subtle you need to add in.

16. zepp

;D

17. zepp

What do we need to say first when you start adding angles to make 5. m∡MYZ = m∡MYX + m∡XYZ Angle Addition Postulate this valid?

18. zepp

When you start adding congruent angles, there's something you'd have to mention.

19. zepp

You'd need to mention that Angle XYZ = Angle XYZ by the reflexive property :)

20. zepp

Since when you substitute m∡NYZ in #5 5. m∡MYZ = m∡MYX + m∡XYZ 6. m∡MYZ = m∡NYZ + m∡XYZ You proved that MYX = NYZ, but not XYZ = XYZ, that what I meant by 'when you start adding congruent angles'.