Transformations of Graphs | GCSE Maths

What are the three types of transformations

The three types of transformations are

  1. Enlargements (stretch)
  2. Translations (movement)
  3. Reflections

How can we tell if a transformation affects the x-coordinates or the y-coordinates?

Transformations outside the bracket affect the y-coordinates

Transformations inside the bracket affect the x-coordinates

When it is inside the bracket, the transformation has the opposite effect to what you'd naturally expect.

If f(x) is the original graph, what is the effect of the following transformations?

f(x) + 21

vertical translation, up by 21

f(x+21) 

horizontal translation, left by 21

2f(x) 

vertical stretch, scale factor 2

f(2x)

horizontal stretch, scale factor 1/2

-f(x) 

vertical reflection

f(-x)

horizontal reflection