Use the theorem that relates the sum of degrees to the number of edges to determine the number of edges in the graph.
-A graph with 8 vertices, two of degree 2, four of degree 3, and two of degree 1.
A)9 edges
B)6 edges
C)3 edges
D)18 edges

Question

Quizplus · Accepted Answer

The sum of the degrees of all vertices in a graph is twice the number of edges. For this graph, the sum of degrees = (2*2) + (4*3) + (2*1) = 4 + 12 + 2 = 18. Therefore, the number of edges = 18 / 2 = 9.

Use the Theorem That Relates the Sum of Degrees to the Number