Step by step
The question
Question: graph y = |x + 4| from y = |x|.
We know the graph of y = |x|.
It is a V, with its corner at (0, 0).
1 Read the changes
Inside, next to x, we have + 4.
x = −4 makes the inside 0.
So the corner moves to x = −4: left 4.
Careful!
Inside, it goes the opposite way to the sign.
2 Start from y = |x|
Draw the grid.
The x-axis goes across.
The y-axis goes up and down.
They meet at 0.
That point is called the origin.
Draw y = |x| first.
Its corner is at (0, 0).
3 Move the corner
Move it left 4.
The new corner is (−4, 0).
4 Draw the new graph
The shape stays the same.
From the corner, 1 right, 1 up.
And 1 left, 1 up.
Join them with the same V.
This is y = |x + 4|.
5 Check
Let's check.
Put x = −4 in the new rule.
We get y = 0: the corner (−4, 0).
And x = −3 gives y = 1: the point (−3, 1) we drew.
Let's look back.
First: read the changes.
Then: start from y = |x|.
Then: move the corner.
Then: draw the new graph.
Last: check.