Slope-Intercept Form Calculator
How It Works
This slope-intercept form calculator uses established formulas to provide accurate results.
The basic rule:
- y = mx + b
- m = (y₂ - y₁) / (x₂ - x₁)
- b = y₁ - m·x₁
Results are estimates. Consult a professional for critical decisions.
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Explore Allday Everyday Math →Frequently Asked Questions
What is slope-intercept form?
Slope-intercept form is y = mx + b, where m is the slope of the line and b is the y-intercept (where the line crosses the y-axis). It is the most common way to write a linear equation.
How do I find b (the y-intercept)?
Once you know the slope m, plug one of your points into y = mx + b and solve for b. So b = y₁ - m·x₁.
Can a vertical line be written in slope-intercept form?
No. A vertical line has an undefined slope, so it cannot be written as y = mx + b. Instead, it is written as x = a constant.
What does the y-intercept tell you?
The y-intercept b is the value of y when x = 0. Graphically, it is where the line crosses the y-axis.