Math 1 · Unit 3 · Lesson 2 · part 1 of 8
The Words We Use
The vocabulary for this lesson, in one place.
Words we use
| Word | Plain English | What you do |
|---|---|---|
| Slope-intercept form | y = mx + b, the form that shows the slope and the y-intercept. | Read m and b straight off it. Graph from it: plot b, step by m. |
| y-intercept (b) | Where the line crosses the y-axis: the value of y when x is 0. The starting value. | Plot it first, at (0, b). |
| Slope (m) | The steepness and direction: rise over run, how much y changes for each step of x. | Step from the y-intercept: rise up or down, run to the right. |
| Starting value | Another name for b in a story: what you have when x = 0. | Read it off the y-axis. |
| Invisible 1 | y = x + 3 means y = 1x + 3, and y = −x means y = (−1)x. | m = 1 or −1. |
| Flat line | y = b with m = 0: no x term. Every point has the same y. | Plot b and step right with no rise. |