Aim: How do we identify transformations?

Transformation:

- A transformation is when you move a geometric figure.

Types of Transformations:

-Translation=Every point is moved the same distance in the same direction

-Rotation=Figure is turned around a single point

-Reflection= Figure is flipped over a line of symmetry

-Dilation=An enlargement or reduction in size of an image 
      

Reflecting over the x-axis: (the x-axis as the line of reflection)

When you reflect a point across the x-axis, the x-coordinate remains the same,
but the y-coordinate is transformed into its opposite. 

The reflection of the point (x,y) across the x-axis is the point (x,-y).      P(x,y) → p' (x,-y) or rx-axis(x,y)=(x,-y)

Hint:  If you forget the rules for reflections when graphing, simply fold your graph paper along the line of reflection (in this example the x-axis) to see where your new figure will be located.  Or you can measure how far your points are away from the line of reflection to locate your new image.  Such processes will allow you to see what is happening to the coordinates and help you remember the rule.