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What is a Diagonal Line?

A diagonal line is a type of line that runs from one corner to another on a piece of paper or other two-dimensional surface. It is not straight, but instead has an angle to it. Diagonal lines can be either horizontal or vertical, depending on how they are drawn.

What is Diagonal Line Example?

A diagonal line is a straight line that goes from one corner of a shape to another. For example, the lines in this square are all diagonal: There are two main types of diagonal lines: those that go from top to bottom ( Rising Diagonals ) and those that go from bottom to top ( Falling Diagonals ).

Here are some examples of each type: Rising Diagonals: Falling Diagonals:

Diagonal lines can be used to create interesting shapes and patterns. For example, the checkerboard pattern is made up of alternating black and white squares, each connected by a diagonal line.

What are Diagonal Lines in Shapes?

In geometry, a diagonal is a line segment joining two vertices of a polygon or polyhedron, when those vertices are not on the same edge. Informally, any sloping line is called diagonal. The word “diagonal” derives from the Greek διαγώνιος (diagonios), “from angle to angle” (in Euclidean Geometry).

The concept of diagonals is represented in various ways. In higher dimensional spaces, diagonals of cubes and hypercubes can be defined similarly: they are line segments joining two vertices that are not on the same face. A skew diagonal is a diagonal that is not perpendicular to any face; more generally it is one that does not intersect any face in its interior.

In matrix algebra, a diagonal matrix is one whose only nonzero entries are on the main diagonal.

What is a Diagonal in Simple Terms?

A diagonal is a line segment joining two vertices of a polygon or polyhedron, when those vertices are not on the same edge. In other words, diagonals are the lines you would draw if you were to connect two opposite corners of a rectangle or square. For example, in the diagram below, the red line segments are diagonals:

The word “diagonal” can also be used more generally to refer to any line segment connecting two points that are not adjacent (i.e., next to each other). So, for instance, the blue line segments in the diagram below are also considered diagonals: The term “diagonal” comes from the Latin word diagonalis, which means “slanting.”

This makes sense when you think about it in terms of geometry: if you were to draw a diagonal line on a piece of paper, it would have a slanted appearance.


A diagonal line is a straight line that connects two opposite corners of a square or rectangle. It is usually drawn from the top left corner to the bottom right corner, or from the top right corner to the bottom left corner.