The linear equation y = mx +b is called slope-intercept form. The slope of the line is m. The y-intercept of the line is b.

Process for graphing lines using slope-intercept form:

Step 1: Write the equation in slope-intercept form. Commonly referred to as "solving for y."

Step 2: Find the slope, or the value of m.

Step 3: Find the y-intercept, or the value of b.

Step 4: Plot the point for the y-intercept at (0, b). Locate a second point using the slope, or .

Example:

Graph the equation 2x + y = 4 using slope-intercept form.

Solution:

Solve for y. y = -2x + 4

Find the slope. m = -2

Find the y-intercept. b = 4 The point (0, 4) is the point at the y-intercept.

Plot the y-intercept and use the slope to find another point on the line.

Assignment:

Graph each equation using the slope and the y-intercept.

1. y = 3x + 1

2. y = -1/2 x + 4

3. y = 3 - x

4. y = 3x

5. y = -1/4 x

6. y = -x - 2

7. y = 4

8. y = -3

9. 12x + 3y = 6

10. 2x - 4y = -4

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