1. Coordinate Grids
Ms. Cuervo

2. Coordinate Grids
7MG 3.2Students will identify, construct, translate, and reflect polygons on the coordinate plane.

3. Vocabulary (Glossary):
Transformation: A movement that does not change the shape of a figure.
Reflection: A transformation that flips a figure across a fixed line of symmetry, obtaining a mirror image.
Translation: A transformation of a figure to a new position without turning or flipping that figure.

4. Example 1 What shape is plotted on the coordinated plane?
What is the distance between the origin and the point (5,0)?
What is the perimeter of the shape?
What is the area of the shape?
(0,5)
(5,5)
(0,0)
(5,0)

5. Vocabulary
A translation involves moving a figure from one location to another, without flipping the figure or changing its shape in anyway.

6. Example 2 Shift the triangle 3 units down and 2 units to the left.
What are the coordinates of A, B, and C?
Where will point A move if the triangle is shifted 3 units down and 2 units to the left? B C A

7. Example 2 (Continued) B B’ C A A’ C’ Steps:
1. Write down the coordinates of the original figure.
2. Translate each point, one at a time.
3. Connect the points to create the new figure.
4. Make sure you include the "prime" symbol for each new point.
The new coordinates are: A' (0, - 1), B' (0, 4), C' (6, -1) B B’ C A A’ C’

8. Reflections
A figure can be reflected across a line of symmetry such as the x-axis, or the y-axis of a coordinate plane.
To reflect a figure, draw each new point on the opposite side of the line of symmetry. The original point and the reflected point must be the same distance from the line of symmetry.

9. Example: Reflect triangle ABC across the x-axis.
1. Find the coordinates for the original figure.
2. How far is each point from the line of symmetry?
3. Your new points should be the same distance from the line of symmetry.
4. Plot your points and connect the points.
HINT: How far is point A from the x-axis? (Point A' should be the same distance from the x- axis). B C A A’ C’ B’