This document contains examples of calculating slope and writing equations of lines from graphs and points. It includes the slope-intercept form equation, examples of finding the slope and y-intercept of lines from their graphs, writing equations of lines given their slope and y-intercept, and finding the slope between two points on a line. Formulas for calculating slope and identifying horizontal and vertical lines are also presented.

1. Graph21Slope:y-intercept:Slope-intercept formy = mx + b-4Example 3-3b

2. 32Graph y = x – 4 32Slope:y-intercept:-4Example 3-3b

3. 43Graph y = - x + 2 43-Slope:y-intercept:2Example 3-3b

4. Graph54-Slope:y-intercept:2Example 3-4a

5. Graph 2x – 5y = 10-2x-2x – 5y = -2x + 10-5-525y = 2 x – 2 5Slope:y-intercept:-2Example 3-4a

6. Slope-intercept formWrite an equation of the line shown in the graph. 42= 2Slope:y-intercept:-3Example 3-2a

7. Answer: Write an equation of the line shown in the graph. 2412--=Slope:y-intercept:3Example 3-2c

8. Write an equation of the line whose slope is and whose y-intercept is –6. Slope-intercept formExample 3-1a

9. GraphTableSlope:-3 2y-intercept:4-3 2y = x + 4Equation:-3 2f(x) = x + 4

10. Find the slope of the line that passes through (–3, 2) and(5, 5). Slope 38Example 1-1a

11. Find the slope of the line that passes through (–3, –4)and(–2, –8). Slope -41Example 1-1a

12. Find the slope of the line that passes through (–3, 4)and(4, 4). Slope 07A horizontal line has a slope of zero.Example 1-1a

13. Find the slope of the line that passes through (2, 4)and(2, 7). 30Slope = undefined30A vertical line has an undefined slope.7 – 4 2 – 2 30=undefinedExample 1-1a