If a graph has 10 vertices how many edges must it have to be a tree

The graph must have 9 edges to be a tree ⇒ 3rd answer

Step-by-step explanation:

* Let us explain how to solve the problem

- Tree with n vertices must have exactly n - 1 edges

- Tree is a connected graph with no cycles

- The edges of a tree are known as branches of the tree

- Look to the attached figure for more understand

* Lets solve the problem

∵ The graph has 10 vertices

∵ In the tree the edges less than the vertices by 1

∴ The number of the edges = 10 - 1 = 9 edges

* The graph must have 9 edges to be a tree