1. Write an equation given the slope and y-intercept EXAMPLE 1 Write an equation of the line shown.

2. SOLUTION Write an equation given the slope and y-intercept EXAMPLE 1 From the graph, you can see that the slope is m = and the y- intercept is b = – 2. Use slope-intercept form to write an equation of the line. 3 4 y = mx + b Use slope-intercept form. y = x + (– 2) 3 4 Substitute for m and –2 for b. 3 4 y = x (– 2) 3 4 Simplify.

3. GUIDED PRACTICE for Example 1 Write an equation of the line that has the given slope and y - intercept. 1. m = 3, b = 1 SOLUTION Use slope – intercept point form to write an equation of the line y = mx + b Use slope - intercept form. y = x + 1 3 Substitute 3 for m and 1 for b. Simplify. y = x + 1 3

4. GUIDED PRACTICE for Example 1 2. m = – 2, b = – 4 SOLUTION Use slope – intercept point form to write an equation of the line y = mx + b Use slope - intercept form. y = – 2x + (– 4 ) Substitute – 2 for m and – 4 for b. Simplify. y = – 2x – 4

5. GUIDED PRACTICE for Example 1 SOLUTION Use slope – intercept point form to write an equation of the line y = mx + b Use slope - intercept form. 3. m = – b = 3 4 7 2 Substitute – for m and for b. 3 4 Simplify. y = – x + 3 4 7 2 7 2 3 4 7 2