An irregular polygon is a polygon where the sides and angles are not all equal

Identify and describe the relationship between irregular polygons using scale factors

Maths

In this unit pupils will describe the relationship between 2 factors using a ratio grid to calculate unknown values They will use their knowledge of multiplication and division to solve scaling problems and identify and describe the relationship between two shapes using scale factors and ratios. In the future unit pupils will link fractions to ratio and look at ratio with exchange and conversions.

 In the prior unit pupils explained why the product stayed the same when one factor is doubled and the other is halved using knowledge of equivalence. They explained the effect on the quotient when scaling the dividend and divisor by the same amount. In this unit pupils will describe the relationship between two factors and use a ratio grid to calculate unknown values. 

Ratio and proportion

Which of these shapes are regular polygons?

Which of these shapes are irregular polygons

A and B are similar rectangles. What is the missing dimension in rectangle B?

This ratio table gives the dimensions of two rectangles. What is the scale factor between the rectangles?

The ratio of height to width in both rectangles is 1 to 2 or 1 : 2

The height of each rectangle is double the width

The width of each rectangle is half the height

What is the relationship between the height and width of both rectangles?

There is lots of information given about this shape. Which bits of information tell you about its dimensions?

Which of these pairs of shapes are similar?

What is the scale factor between hexagons A and B?

What number is one and a half times the size of 6?

Which of these shapes is similar to triangle A with a scale factor of 4?

Which of these shapes is similar to square A with a scale factor of one half?

This lesson will soon be taken down.

Identify and describe the relationship between irregular polygons using scale factors

Lesson outcome