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A graph is a set of points, called vertices or nodes, connected by lines called edges or arcs. A simple graph is one that has no loops and in which no pair of vertices are connected by more than one edge. The number of edges incident on a vertex is called its order, degree or valency.

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of two vertices if there is a path between them.


On a graph: the number of edges incident to a vertex.
In geometry: a measure of angle


the line connecting two vertices of a graph, also known as arc or line.


A diagram showing a relationship between two variables.
The diagram shows a vertical y axis and a horizontal x axis.


The number of edges incident to a vertex.


A point or node of a graph.

Full Glossary List

This question appears in the following syllabi:

SyllabusModuleSectionTopicExam Year
Edexcel A-Level (UK - Pre-2017)D1Algorithms on graphsPlanarity-
I.B. Higher Level10Algorithms on graphsPlanarity-
OCR A-Level (UK - Pre-2017)D1Algorithms on graphsPlanarity-
OCR-MEI A-Level (UK - Pre-2017)D1Algorithms on graphsPlanarity-
Universal (all site questions)AAlgorithms on graphsPlanarity-
Edexcel AS Further Maths 2017Decision Maths 1Algorithms on GraphsPlanarity-
AQA AS Further Maths 2017Discrete MathsNetworksPlanarity-
OCR AS Further Maths 2017Discrete MathsNetwork AlgorithmsPlanarity-
OCR MEI AS Further Maths 2017Modelling with AlgorithmsNetworksPlanarity-
Edexcel AS/A2 Further Maths 2017Decision Maths 1Algorithms on GraphsPlanarity-
AQA AS/A2 Further Maths 2017Discrete MathsNetworksPlanarity-