1. 9-3 Rotations
Vocab
Rotation: A transformation that turns a shape on an axis
Center of rotation: The point at which a rotation is turned
Angle of rotation: The number of degrees a shape is rotated

2. Types of Rotations 90°: (x,y) becomes (-y,x)
180°: (x,y) becomes (-x,-y)
270°: (x,y) becomes (y,-x)
Ex 1: Given points (1,1) (4,5) and (5,1), rotate the triangle 90°
Ex 2: Given points (1,1) (4,5) and (5,1), rotate the triangle 180°
Ex 3: Given points (1,1) (4,5) and (5,1), rotate the triangle 270°

3. Rotation Word Problems
Ex 4: A damaged compass points northwest. If you travel west by the compass, what is your angle of rotation to true north?
Ex 5: A circular dial with the digits 0 through 9 evenly spaced around its edge can be rotated clockwise 36°. How many times would you have to perform this rotation in order to bring the dial back to its original orientation?

4. Classwork/Homework P