Warm-up # 4 5 −3= Write the slope-intercept form for the equation of the line through (0, 2) that has a slope of 3 4 Write the slope-intercept form for the equation of the line through the points (5, 0) and (-3, -1).

Homework Lesson 4.03_page 286 #1a-d and 2a-d

Lesson 4.3: Graph using Slope-Intercept Form

we can graph a line easily when given: 1. a random point 2. the slope of the line

SLOPE-INTERCEPT FORM

y = mx + b STEP 1: Look at the y-intercept (b): When you have a linear equation, the y-intercept is the point where the graph of the line crosses the y-axis. STEP 2: Look at the slope (m): It describes the steepness of a line. You use “rise over run”

Example 1 y = 𝟐 𝟑 x + 2

Example 2 y = 3x - 1

Example 3: Now we can finally graph using slope-intercept form. y = mx + b y = -3x + 2 m =-3= −3 1 b = 2= (0,2)

Example 4: Graph using slope-intercept form. y = mx + b x + y = 0 y = -x m = -1= −1 1 b = 0= (0,0)

Example 5: Graph using slope-intercept form. 4x + 5y = 15 -4x -4x 5y = -4x + 15 5 5 5 𝐲= −𝟒 𝟓 𝐱+𝟑 m = −4 5 b = 3= (0,3)

Example 6: Graph using slope-intercept form. 4x - y – 3 = 0 -4x -4x - y – 3 = -4x +3 +3 -y = -4x + 3 y = 4x -3 m = 4 = 4 1 b = -3= (0,-3)