Translations and Reflections Section 11 – 8 & 11 – 9

Transformations A transformation occurs when a point or figure moves from it original position.  Translation – a slide for a point or the figure  Reflection – a transformation of a point or figure over a ‘line of reflection’.  Line of Reflection – line over which a point or figure is reflected.

What is a translation? A translation is a starting point and ending point. Move right – a positive change in x. Move left – a negative change in x. Move up – a positive change in y. Move down – a negative change in y. * The new point will have ( ’ ) –Ex: A will become A’ (called A prime)

What is a reflection? A reflection is a mirror image of the original point or figure. How do you find the new point? –Count the number of units it is for the point to get to the ‘line of reflection’ –Count the SAME number of units away from the line of reflection. –Identify the new ordered pair.

Tricks of the trade Count the lines, not the empty spaces. DO NOT include the line you start on. Remember, left/right, then up/down Move left yields a negative x Move right yields a positive x Move up yields a positive y Move down yields a negative y

Practice What’s the ordered pair if reflected across the x – axis ? What’s the ordered pair if reflected across the y – axis ? What quadrant is it in?

O A B F G A’ F’ B’ G’

Where am I? M (– 4, 5); translated 3 units left, and three units down. T (– 2, – 5); slides up six units, and right two units. R (3, – 3); translated left 7 units and up 8.

O M R T R’ M’ T’

Final Reminders! Identify quadrants with Roman Numerals –If a point is on an axis, then name the ‘axis’ that it is on! The proper way to write an ordered pair: ( x, y). Each x, or y represents a line, not a space. Label both axis.

Homework Worksheet Food for thought: –What are the signs of the x and y values when you are in quadrant: I? II? III? IV?