Chapter 9 - Transformations
Chapter 9 - Transformations
90 degree rotation(x1, y1)
180 degree rotation(x2, y2)
270 degree rotation(x3, y3)
9.3 - Rotations (notation)
• Correct Notation = r (angle, point) {object}
• r(90, O) ABCD This “rotates” the quadrilateral ABCD an angle of 90 degrees counter-clockwise around the origin.
• r(180, O) ABCD This “rotates” the quadrilateral ABCD an angle of 180 degrees counter-clockwise around the origin.
Section 9.3 – Rotation Rules
Section 9.3 – Rotation Rules
Rotating an Object around the Origin
r(90,O) ABC
x
yScale is 1 by 1
A
B C
A’B’
C’
r(180,O) ABC
r(270,O) ABCA”
B”C”
A’’’B’’’
C’’’