How_To_Be_Good_At_Math

206 GEOMETRY • DIAGONAL LINES

Parallel lines

A straight line that slants is called a diagonal line.

A diagonal line is not vertical or horizontal. Another

name for a diagonal line is an oblique line.

Diagonals inside shapes

In geometry, the word diagonal has

another, more exact meaning.

Angles on a straight line

shape. It joins two corners that are

not next to each other.

Straight lines can be

horizontal, vertical,

or diagonal.

Here are some examples of a

diagonal inside a shape. We have

shown one diagonal on each shape.

The more sides a shape has, the

more diagonals it will have.

Look at this picture of a zip

wire. It is made of horizontal,

vertical, and diagonal lines.

Diagonal

Diagonal

Diagonal

206_207_Diagonal_lines.indd 206 29/02/2016 18:04