Step by step
The question
Question: reflect the shape A(3, 0), B(5, 2) and C(3, 2) in the x-axis.
1 Draw the shape
Put the points on the grid and join them.
2 Draw the mirror line
The mirror line is the x-axis.
Reflecting flips the shape over the line, like a mirror.
Each point lands just as far away, on the other side.
3 Reflect each point
A is on the mirror line.
It stays where it is: A'(3, 0).
From B, count straight to the mirror line: 2.
Then count 2 more on the other side.
We call the new point B prime.
The little mark means: the new B.
B is 2 above the x-axis.
Its image is 2 below it.
Its x stays 5.
So B' is (5, −2).
Careful!
The x-axis is flat.
The flip goes up or down, so y changes.
x stays.
C is 2 above it, so C' is 2 below: (3, −2).
4 Draw the image
Join the new points.
This new shape is called the image.
So the image is A'(3, 0), B'(5, −2) and C'(3, −2).
5 Check
Let's check with the rule for the x-axis: x stays the same, y changes sign.
It gives the same points.
Right!
Let's look back.
First: draw the shape.
Then: draw the mirror line.
Then: reflect each point.
Then: draw the image.
Last: check.