ALGEBRA 1 LESSON 6 2 SlopeIntercept Form What

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form What are the slope and y-intercept of y = 2 x – 3? = mx+b Use the Slope-Intercept form. = 2 x– 3 The slope is 2; the y-intercept is – 3. 6 -2

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form 2 Write an equation of the line with slope and 5 y-intercept 4. y = mx + b 2 5 y= x+4 Use the slope-intercept form. Substitute 2 for m and 4 for b. 5 6 -2

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form Write an equation for the line. Step 1 Find the slope. Two points on the line are (0, 1) and (3, – 1). slope = =– Step 2 – 1 3– 0 2 3 Write an equation in slope– intercept form. The y-intercept is 1. y= mx+b y=– 2 x+1 3 6 -2 Substitute – 2 for m 3 and 1 for b.

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form Graph y = Step 1 The y-intercept is – 2. So plot a point at (0, – 2). 1 x – 2. 3 Step 2 Step 3 1 The slope is. 3 Use slope to Draw a line through plot a second point. the two points. 6 -2

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form The base pay for a used car salesperson is $300 per week. The salesperson also earns 15% commission on sales made. The equation t = 300 + 0. 15 s relates total earnings t to sales s. Graph the equations. Step 1 Identify the slope and y-intercept. t = 300 + 0. 15 s t = 0. 15 s + 300 Rewrite the equation in slope intercept form. slope y-intercept 6 -2

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form (continued) Step 2 Plot two points. First plot a point at the y-intercept. Then use the slope to plot a second point. The slope is 0. 15, which equals Plot a second point 15 units above and 100 units to the right of the y-intercept. Step 3 Draw a line through the points. 6 -2 . 15 100

ALGEBRA 1 LESSON 6 -2 Slope-Intercept Form Find the slope and y-intercept of each equation. 3 4 1. y = 3 x – 3 m = ; b = – 3 2. y = – 2 x m = – 2; b = 0 4 5. Write an equation for the line. y= 1 x– 3 2 Write an equation of a line with the given slope and y-intercept. 3. m = – 3, b = – 4 y=– 3 x– 4 4. m = 0. 5, b = 1 y = 0. 5 x + 1 5 5 6. Graph y = –x + 3. 6 -2