Compute the Sum of the Degrees of All Vertices and count Number of Edges

Question

Can someone help me understand this problem? The question asks: For the following three graphs, (a) compute the sum of the degrees of all the vertices, (b) count the number of edges and look for a pattern for how the answers to (a) and (b) are related.

The graph is below

I have no idea how to solve for sum of degrees when there are no numbers given in that graph. Additionally, the materials I am reading on sum of degrees is difficult to comprehend. I would love to get a Layman's term style of understanding how to go about solving this problem.

Answer 1

The degree of a node is th number of connected lines. Look at the following picture to got a feeling for what I mean. The upper red node is of degree two because two lines (edges) are connected. The middle green one is of degree three, because it touches three lines.

Just sum up all degrees of all nodes to find your result.

Answer 2

The degree of a vertex (dot) is the number of edges (lines) that touch the vertex.

For any graph the sum of the degrees of the vertices equals twice the number of edges (Euler, $1736$).