# Coordinate Rules for Rotations. 43210 In addition to 3, I am able to go above and beyond by applying what I know about coordinate rules for performing.

## Presentation on theme: "Coordinate Rules for Rotations. 43210 In addition to 3, I am able to go above and beyond by applying what I know about coordinate rules for performing."— Presentation transcript:

Coordinate Rules for Rotations

43210 In addition to 3, I am able to go above and beyond by applying what I know about coordinate rules for performing transformations and could teach someone else. Use coordinates to write directions for drawing figures, specify the coordinates of the original and new image under a transformation and specify the coordinate rules for those transformations. I can use coordinates for drawing figures. I can specify coordinates of the new image after the transformation. I can specify the rules for the transformations. I have partial understanding of how to use coordinates to write directions for drawing figures, specify the coordinates of the original and new image under a transformation and specify the coordinate rules for those transformations. With help I may have a partial understanding of how to use coordinates to write directions for drawing figures and specify the coordinates of the original and new image under a transformation. Even with help, I am not able to use coordinates to write directions for drawing figures nor specify the coordinates of the original and new image under a transformation. Learning Goal 1 (8.G.A.3): Use coordinates to write directions for drawing figures, specify the coordinates of the original and new image under a transformation and specify the coordinate rules for those transformations.

A Rotation is… A rotation is a transformation that turns a figure around a fixed point called the center of rotation. A rotation is clockwise if its direction is the same as that of a clock hand. A rotation in the other direction is called counterclockwise. A complete rotation is 360˚.

Before rotating a figure about the origin on a coordinate grid… Estimate what quadrant the figure will end up in. It may help to draw a line from one vertex of the object to the origin. What quadrant would 90˚ clockwise rotation end up in? –Imagine making a right angle with the line. –It will end up in quadrant 4. What do you notice about the two triangles?

Before rotating a figure about the origin on a coordinate grid… Estimate what quadrant the figure will end up in. It may help to draw a line from one vertex of the object to the origin. What quadrant would 180˚ counter-clockwise rotation end up in? –Imagine making a straight angle with the line. –It will end up in quadrant 3. What do you notice about the two triangles?

Goal: accurately rotate an object about the origin and specify the ordered pairs of the new shape. As we go through the next few examples, try to look for a pattern or relationship between the ordered pairs after each rotation. Pass out Labsheet 3.3

Rotate points A-E 90˚ counterclockwise about the origin. Which quadrant will it end up in? Write a rule for the pattern relating the coordinates of key points to the coordinates of their image after a 90˚ rotation: (x, y) → Do any points remain unchanged after this rotation? Do the flag and its image make a symmetric design? (5, 4)(6, 6)(3, 6) (0, 0) (-4, 2 ) (-4, 5 ) (-6, 6) (-6, 3) (-y, x) B’ C’ D’ E’ A’

Rotate points A-E 180˚ counterclockwise about the origin. Which quadrant will it end up in? Write a rule for the pattern relating the coordinates of key points to the coordinates of their image after a 180˚ rotation: (x, y) → Do any points remain unchanged after this rotation? Do the flag and its image make a symmetric design? (5, 4)(6, 6)(3, 6) (0, 0) (-2, -4 ) (-5, -4) (-6, -6) (-3, -6) (-x, -y) B’ C’ D’ E’ A’

When you rotate a figure 180˚, does it matter whether you rotate clockwise or counterclockwise? Compare  E to  E’,  D to  D’, and  C to  C’. What do you notice about each angle pair? What effect do rotations have on angles? What effect do rotations have on side lengths? B’ C’ D’ E’ A’

Download ppt "Coordinate Rules for Rotations. 43210 In addition to 3, I am able to go above and beyond by applying what I know about coordinate rules for performing."

Similar presentations