Explore
Transformations on the Coordinate Plane Solutions
The Coordinate Plane is made up by a horizontal number line, the x -axis , and a vertical number line, the y -axis .
Each coordinate ( x , y ) represents a point on the coordinate plane.
A reflection is a mirror image after a shape or graph has been flipped over the line of reflection.
To reflect a figure over the x -axis:
Label each vertex as x , y .
Each point x , y will become ( x , – y ) in the reflected image.
To reflect a figure over the y-axis
Label each vertex as x , y .
Each point x , y will become ( – x , y ) in the reflected image.
A translation is a shift , either horizontal, vertical, or both, on the coordinate plane.
To translate a point horizontally:
Subtract the horizontal translation from the x -coordinate to move the point to the left.
Add the horizontal translation to the x -coordinate to move the point to the right.
To translate a point vertically:
Subtract the vertical translation from the y -coordinate to move the point down .
Add the vertical translation to the y -coordinate to move the point up .
To translate a figure, translate each vertex based on the given translation.
Example 1
Reflect or translate the coordinate ( – 3 , 5 ) on the graph.
Reflect over the x -axis. Plan: x , y → x , – y
Translate right two units, down eight units. Plan: Translate right: add 2 units to x -coordinate Translate down: subtract 8 units from y -coordinate.
Translate left three units, up one unit.
Plan:
Translate left: subtract 3 units from x -coordinate
Translate up: add 1 unit to y -coordinate.
Example 2
Reflect the figure over the given axis.
Reflect the figure over the x -axis.Plan:
Label each vertex x , y . Plot the reflected points x , – y .
– 4 , 5 → – 4 , – 5 2 , 3 → 2 , – 3 – 5 , 2 → – 5 , – 2
Reflect the figure over the y -axis. Plan:
Label each vertex ( x , y ) . Plot the reflected points ( – x , y ) .
– 4 , 5 → 4 , 5 2 , 3 → – 2 , 3 – 5 , 2 → 5 , 2
Example 3
Translate the figure.
Translate 5 units right and 6 units down.
Plan : Label each vertex ( x , y ) . Shift each vertex ( x + 5 , y – 6 ) .
– 5 , 0 → – 5 + 5 , 0 – 6 → 0 , – 6 – 5 , 5 → – 5 + 5 , 5 – 6 → 0 , – 1 – 2 , 5 → – 2 + 5 , 5 – 6 → 3 , – 1 – 2 , 0 → – 2 + 5 , 0 – 6 → 3 , – 6