Slope-Intercept Form
Line with slope m and y-intercept b.
Key idea
Line with slope m and y-intercept b.
In depth
y = mx + b shows the slope m and the y-intercept b, where the line crosses the y-axis. You can graph it by plotting b and then moving using the slope.
Worked example
y = 2x − 3: start at (0, −3), go up 2 and right 1 to (1, −1).
Formula
Real-world uses
- Writing a taxi fare formula with a starting fee plus cost per km
- Predicting values from a trend line
Common mistake
Reading b as the x-intercept.
How to learn this
- Read the key idea and say it in your own words.
- Work through the worked example, then try a similar problem.
- Use the interactive lesson’s visual and mini-quiz to check the pattern.
Frequently asked questions
What is Slope-Intercept Form?
Line with slope m and y-intercept b. It is a topic at the intermediate level in Algebra.
What is the formula for Slope-Intercept Form?
The key formula is y = mx + b.
Where is Slope-Intercept Form used in real life?
Real-world examples: Writing a taxi fare formula with a starting fee plus cost per km; Predicting values from a trend line.
What should I learn before Slope-Intercept Form?
Make sure you are comfortable with Slope, the previous topic in Algebra.
What is a common mistake with Slope-Intercept Form?
Reading b as the x-intercept.
How can I practise Slope-Intercept Form?
Open the interactive lesson, play with the visual, then answer the three-question mini-quiz. Getting two right marks the topic complete.
What comes after Slope-Intercept Form?
Move on to Point-Slope Form next.
Related intermediate topics in Algebra
- Multi-Step Equations – Distribute, combine like terms, move variables to one side.
- Variables on Both Sides – Collect variable terms on one side first.
- Literal Equations – Rearrange formulas to solve for a chosen variable.
- Identity and No-Solution Equations – Some equations are always true or never true.
- Linear Inequalities – Solve like equations but reverse the sign when multiplying by a negative.
- Compound Inequalities – Combine two inequalities using “and” or “or”.