# Coordinate polygons

## In a nutshell

Using your knowledge of polygons, you can find the missing points of a shape. Regular polygons have equal length sides and angles. Irregular polygons may also have special properties which will allow you to complete the shape.

## Completing a square

A square has four sides of equal length. By using three coordinates, you can find the final coordinate to complete the square.

##### Example 1

*On the grid below is square $ABCD$. Find the coordinate of point $B$.*

*As a square is a polygon the missing coordinate will be five spaces to the left of coordinate *$A$* and five spaces below coordinate *$C$*.*

$\underline{B:(2,2)}$

## Missing coordinates for an irregular polygon

Irregular polygons* *also have special features. The opposite sides of a parallelogram are parallel to each other, which means they go in the same direction.

##### Example 2

*Find the coordinate which would complete the parallelogram below.*

**$\underline{(6,9)}$**

**Note: **If you extend parallel lines in both directions, they will always be the same distance from each other.

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