Steply

Graph 2x + 3y = 6

Step by step, with the reason for every step · Graphing Ax + By = C · Algebra 1

Step by step

The question

Question: graph 2x + 3y = 6.

2x + 3y = 6

Every point on the x-axis has y = 0.

Every point on the y-axis has x = 0.

on the x-axis: y = 0
on the y-axis: x = 0

1 Cross the x-axis

On the x-axis, y = 0.

Put 0 in place of y.

2x + 3 × 0 = 6

3 times 0 is 0.

Adding 0 changes nothing.

2x = 6

2x means 2 times x.

We want just x.

To remove times 2, we divide by 2.

We do it on both sides, so they stay equal.

2x2 = 62

2 divided by 2 is 1.

So just x is left.

6 divided by 2 is 3.

62 = 3

So x = 3.

x = 3

So the line crosses the x-axis at (3, 0).

This point is called the x-intercept.

→ (3, 0)

2 Cross the y-axis

On the y-axis, x = 0.

Put 0 in place of x.

2 × 0 + 3y = 6

2 times 0 is 0.

0 plus 3y is just 3y.

3y = 6

3y means 3 times y.

We want just y.

To remove times 3, we divide by 3.

We do it on both sides, so they stay equal.

3y3 = 63

3 divided by 3 is 1.

So just y is left.

6 divided by 3 is 2.

63 = 2

So y = 2.

y = 2

So the line crosses the y-axis at (0, 2).

This point is called the y-intercept.

→ (0, 2)

3 Draw the line

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 two points on the grid: (3, 0)

and (0, 2).

Join the dots with a straight line.

It keeps going both ways.

4 Check

Let's check with another point on the line: (−3, 4).

It sits on a grid corner.

Put x = −3 and y = 4 into 2x + 3y.

2(−3) + 3(4) = −6 + 12 = 6

We get 6, the same as the right side.

So the line is right!

Let's look back.

First: cross the x-axis.

Then: cross the y-axis.

Then: draw the line.

Last: check.

Answer
y = 2

Your turn

Try this one yourself, then check:

Graph 3x + 4y = 12
Show the answer
crosses at (4, 0) and (0, 3)

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