
# 4.A: Reflections and Translations


## Overview

The purpose of this lesson is to learn how to represent reflections and translations on the coordinate plane.

This lesson will address the following CCRS Standard(s) for Geometry:

• 8.G.2: Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them

## Directions

1. Take notes while watching videos below
2. Go to http://wamap.org and log into our course to complete assignment 4.A with 80% or better.

### Watch

Reflections and Translations [9:51]

### Do

Complete assignment 4.A with 80% or better at http://wamap.org

## Summary

In this lesson we have learned:

• Reflections create a mirror image of the original shape which is congruent to the original shape
• Reflecting (a,b) over the x-axis gives the point (a,-b)
• Reflecting (a,b) over the y-axis gives the point (-a,b)
• Reflecting (a,b) over the origin gives the point (-a,-b)
• Reflecting (a,b) over the line y=x gives the point (b,a)
• Translations slide the original shape creating a second congruent shape
• Translating (a,b) up c and right d units gives (a+d,b+c)

4.A: Reflections and Translations is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.