Download 9.3 Perform Reflections

9.3 Perform Reflections
Example 1: Graph the reflections in horizontal and vertical lines
The vertices of ∆ABC are A(1,3), B(5,2), and C(2,1). Graph the reflection of ∆ABC described.
a. Line of reflection: x=3
b. Line of reflection: y = 1
Example 2: Graph a reflection in y = x and y = -x
The vertices of ∆FGH are F(-1, 2), G(1,2), and H(-1,1). Graph the reflection of ∆FGH described.
a. Line of reflection: y = x
b. Line of reflection: y = -x
Example 3: Graph two reflections
The vertices of ∆FGH are F(3,2), G(1,5), and H(-1,2). Reflect ∆FGH in the first line. Then reflect ∆F’G’H’ in the second
line.
First Line of Reflection: y = 2
Second Line of Reflection: y = -1
Coordinate Rules for Reflection
 If (a,b) is reflected in the x-axis, its image is the point (a,-b)
 If (a,b) is reflected in the y-axis, its image is the point (-a,b)
 If (a,b) is reflected in the line y = x, its image is the point (b,a)
 If (a,b) is reflected in the line y = -x, its image is the point (-b,-a)