## BIGDOG96 3 years ago Prove that the opposite angles of a parallelogram are congruent.

1. BIGDOG96

2. BIGDOG96

Can anyone help?

3. mayankdevnani

Well, that's a property of parallelograms.

4. mayankdevnani

But if you must prove it, I say you draw a diagonal from one angle to the opposite one, and then prove that the two triangles formed are congruent, since their three sides have the same length.

5. mayankdevnani

After that, just prove that the opposite angles are congruent because correspondent angles on congruent triangles are congruent.. @BIGDOG96

6. jiteshmeghwal9

|dw:1347976457702:dw|

7. jiteshmeghwal9

so here through this congruency it is proved that opposite angles of a parallelogram are always equal.

8. BIGDOG96

Thanks

9. jiteshmeghwal9

yw :)

10. mayankdevnani

welcome...

11. BIGDOG96

I get it better with the pic

12. BIGDOG96

Is there anyway you could write out the steps, they kinda got chopped off. @jiteshmeghwal9

13. jiteshmeghwal9

yes!

14. jiteshmeghwal9

write my first & second replies

15. jiteshmeghwal9

cleanly,in ur note-book

16. jiteshmeghwal9

they are the steps :)

17. BIGDOG96

Is any of that missing?

18. BIGDOG96

Is this right? First draw two bisectors in the parallelogram. So, here is a parallelogram namely ABCD. angle 5 = angle 4 alternate interior angles congruency. 1 - 2 - angle 6 = angle 3 alternate interior angles congruency. 3 -angle 1 = angle 8 alternate interior angle congruency. 4 - angle 2 = angle 7 alternate interior angle congruency.

19. jiteshmeghwal9

yes!

20. BIGDOG96

Okay thanks. Can you help with another one?

21. jiteshmeghwal9

Hmm! if the question is not same then i will help you because i have cleared ur concept :)

22. jiteshmeghwal9

in this type of question

23. BIGDOG96

Will you check my work?

24. jiteshmeghwal9

ok!