Step by step
The question
Question: find the horizontal line through (5, 0), and graph it.
A new word: horizontal.
It means flat, going across.
1 Write the equation
A horizontal line is flat.
Every point on it is right beside (5, 0), at the same height.
So every point has the same y: 0.
So the line is y = 0.
y = 0 has no x in it.
So x can be any number.
But y is always 0.
2 Make points
Let's make some points.
Every point has y = 0.
For x, we pick any numbers: 1, 3 and 5.
3 Plot the points
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.
Put the points on the grid: (1, 0),
(3, 0),
and (5, 0).
They stand in a row, right beside each other.
4 Draw the line
Join the dots.
The line goes flat, across.
It is a horizontal line.
It never goes up, so its slope is 0.
The line lies right on the x-axis.
So y = 0 is the x-axis itself.
Careful: y = 0 does not go up and down.
It is flat.
5 Check
Let's check one more point on the line: (4, 0).
Its y is 0.
So it fits y = 0.
The line is right!
Let's look back.
First: write the equation.
Then: make points.
Then: plot the points.
Then: draw the line.
Last: check.