Reflections across f(x) = -x
Directions
Points C, D, and E are graped above.
The line or is graphed aboved.
Reflect points C,D, & E over the line.
1) Click on the "reflection about line" tool
2) Click on the line of reflection then
3) Click on the point you want to reflect
These steps should plot the pre-images C', D' and E'.
Observation
What do you notice about the pre-image and image coordinates? Based on your observations, write a rule describing how the coordinates change when reflected over the line .
PRACTICE: f(x) = -x reflections
Use the graph below to answer the questions that follow.
Question 1
Trapezoid MNOP has vertices at M(1, 0) N(7, 0) O(5, 3) P(3, 3) What are the coordinates of Trapezoid M'N'O'P' given a reflection across the line f(x) = -x?
Question 2
Triangle XYZ has vertices at X(8, 8) Y(8, 0) Z(4, 0) What are the coordinates of Triangle X'Y'Z' given a reflection across the line f(x) = -x?