➕ Algebra 1 · Linear Functions
Slope-Intercept Form cheat sheet
Everything you need on one page. Print it, or switch on test-yourself mode to blur the answers and check your memory.
The form
- y = mx + b
- m = slope = rise ÷ run
- b = y-intercept: the line crosses the y-axis at (0, b)
Write an equation
- 1. Find m (slope formula if you have two points)
- 2. Put m and one point (x, y) into y = mx + b
- 3. Solve for b
- 4. Write y = mx + b and check
In a story
- m = rate of change (“per”)
- b = starting value (when x = 0)
- Give the units
Special lines
- Horizontal: y = b, slope 0
- Vertical: x = a, slope undefined, not in this form
Example
- Points (−2, −1) and (4, 8)
- m = 9/6 = 3/2
- 8 = (3/2)(4) + b, so b = 2
- y = (3/2)x + 2
Formulas
- Slope-intercept form: y = mx + b
- Finding b from a point: b = y1 − m × x1, using any point (x1, y1) on the line
- Horizontal line: y = b, slope 0
- Vertical line: x = a, slope undefined, not in slope-intercept form
Slope-Intercept Form cheat sheet from HighSchoolQ.com, for personal study use.