## anonymous one year ago Plz check this for me

1. anonymous

2. anonymous

My Question in image plz

3. ganeshie8

Degree of a vertex is the number of incident edges. Notice that the degree of each vertex in the new graph is $$4$$ : |dw:1438553486134:dw|

4. anonymous

5. ganeshie8

Since there are $$45$$ vertices, the sum of degrees is $$4\cdot 45 = 180$$

6. anonymous

The sum of the degrees is 4 · = , so the number of edges is , by Theorem 2.6

7. anonymous

and number of edges?

8. ganeshie8

Are you looking for just answer and not really willing to learn ?

9. anonymous

no i want to understand also, I am trying to follow u

10. ganeshie8

good, then look up in ur textbook and tell me what that theorem2.6 is about

11. anonymous

okay

12. anonymous

here is theorem

13. ganeshie8

That theorem says, sum of degrees = $$2|E|$$ $180=2|E| \implies |E| = 90$

14. anonymous

hmmmm

15. ganeshie8

Btw, $$E$$ is the set of edges. $$|E|$$ is a symbol that represents the number of elements in the set $$E$$

16. anonymous

so it is like 4.45=180 and90

17. ganeshie8

Yep!

18. anonymous

thank you... :)