## Squirrel02 3 years ago Can someone help me please?? What else must you know to prove the triangles congruent by SAS? Diagram will be in the comments. So, please wait a few minutes.

1. AravindG

wow charizarD!!!

2. Squirrel02

|dw:1352307435101:dw| Diagram is not to scale. Sorry, I messed up on the size a bit.

3. Squirrel02

Yup! ^^ Is Charizard your favorite pokemon too?

4. AravindG

yaaaa!!! love it a lot!!

5. Squirrel02

Thanks! ^^ Can you help me out with this problem?

6. Squirrel02

I know that SAS stands for Side-Angle-Side. I need the following: a) 2 congruent corresponding sides b) 2 congruent corresponding angles c) 2 congruent corresponding sides

7. Squirrel02

I believe that angles A and C are congruent to one another would account for b).

8. Squirrel02

I don't know how to find the sides exactly though.

9. AravindG

2 congruent corresponding sides

10. Squirrel02

Yes

11. emcrazy14

AC is shared by both the triangles. AD is equal to BC as this looks like a rhombus.

12. Squirrel02

@emcrazy14: Okay, so it would be something like this: a) 2 Congruent Corresponding Sides: AD is congruent to BC b) 2 Congruent Corresponding Angles: A is congruent to C c) 2 Congruent Corresponding Sides: CD is congruent to BA ? In a similar problem, someone told me that one of these terms would be uncertain. That we wouldn't be able to prove it without more information given. Therefore, that would be the information we would need that is asked for in the question. How would that be for this problem exactly?

13. Squirrel02

What do you guys think?

14. Jas9420

Lol, the 'Ignore please' cracked me up! :'D

15. Squirrel02

Lol, thanks. ^^;

16. emcrazy14

You see for the SAS property, you need to prove all three things. Two sides and the included angle between them should be proven congruent. So you don't need to tell whether CD is congruent to BA or not.

17. Squirrel02

So, they can all be proven by just looking at the diagram and deciphering it? It's not that some of them cannot be proven at all without further information?

18. emcrazy14

Yes. If a question asks you to prove congruency of the triangles, then there must be some property that enabbles you to do it withot further information. It would be either SAS, SSS, RHS or AAS property!

19. Squirrel02

Okay, I'm just confirming since I may have gotten a different problem wrong due to this. Would it be the same if the question stated "What other information do you NEED in order to prove the triangles congruent using the SAS Congruence Postulate?" What does the RHS stand for? I have not learned about that yet. I understand what you are mean.

20. emcrazy14

RHS Property- If the hypotenuse and a side of a right-angled triangle are equal to the side and hypotenuse of another triangle, then they are congruent. As for your question, no.If a question is phrased like that, then there must be something missing according to that particular postulate, in this case SAS. So, you'll have to find that out and state it.

21. Squirrel02

Okay, then that question is good. For original question stated in this thread, a) 2 Congruent Corresponding Sides: AD is congruent to BC b) 2 Congruent Corresponding Angles: A is congruent to C c) 2 Congruent Corresponding Sides: CD is congruent to BA Is that sufficient for the answers?

22. emcrazy14

(a) and (b) are correct. For (c) you should state that side AC belongs to both triangles. I already told you the angle and the sides making that angle should be congruent.

23. Squirrel02

Wouldn't stating that side AC belongs to both triangles go along with (b)? You are talking about side AC correct?

24. emcrazy14

No. (b) is about the congruent angles. <DAC=<ACB are congruent as they are alternate angles between parallel lines. AC is the congruent side which goes for (c).