How to Find the Equation of a Line

Finding the Equation of a Line

We can find the equation of a line.

The equation will be a linear equation.

How to Find the Equation of a Line

Finding the equation of a line is easy.

Question

What is the equation of the line shown below?

Step-by-Step:

1

Find the y-intercept of the line.

Find where the line crosses the y-axis.

The y-intercept is 1

In our example, the y-intercept is 1.

2

Find the slope of the line.

Slope = How far up ÷ How far across

Slope = 4 ÷ 2

Slope = 2

In our example, the slope is 2.

Write the linear equation. The slope-intercept form of a linear equation looks like:

y = slope x + y-intercept

3

Write y = x with space before the x:

4

Write the y-intercept from Step 1 (1) after the x.

Note: The y-intercept is + 1 because it is 1 above the x-axis. It would be −1 if it was 1 below the x-axis.

5

Write the slope from Step 2 (2) before the x.

Answer:

The equation of the line is y = 2x + 1.

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See Also

What is an equation? What is a linear equation? What is the y-axis? What is the x-axis?