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
Triangle ABC has vertices located at A(9, 0) B(4, 1) C(5, 3) What are the vertices of Triangle A'B'C' given a reflection across the line f(x) = x?
Question 2
Rectangle WXYZ has vertices located at W(0, 0) X(5, 0) Y(5, 5) Z(0, 5) What are the vertices of Rectangle W'X'Y'Z given a reflection across the line f(x) = x?