Volunteers to the board!!  Warm ups Volunteers to the board!!  Graph using intercepts: 2x + 3y = 12 4x – 5y = 20 2x – y = -4 3x + 4y = -8

Convert Standard to Slope-Intercept Objective: To convert a linear equation from standard form to slope-intercept form.

What is the slope of #1? _____ Part of being able to analyze a graph is being able to say the slope. Also, sometimes it is easier to graph with the slope and y-intercept than with the x-and y-intercept. Writing an equation from a graph is easier to do with slope and y intercept (y = mx + b) You will have to do this on your test! -2/3

Convert Standard Slope-Intercept y = mx + b Ax + By = C Steps: 1. Subtract Ax 2. Divide everything by B y = mx + b Ax + By = C

Example 1 Convert the equation from standard form to slope-intercept form: 2x + 3y = 12 -2x -2x 3y = -2x + 12 3 3 3 y = -2x + 4 3 Steps: Subtract Ax Divide everything by B Ax + By = C

Example 2 Convert the equation from standard form to slope-intercept form: 2x – y = -4 -2x -2x -y = -2x – 4 -1 -1 -1 y = 2x + 4 Steps: Subtract Ax Divide everything by B Ax + By = C

TOO Convert to slope-intercept form: 4x – 5y = 10 Now, identify the slope and y-intercept: (hint: slope is m, y-intercept is b) Slope:______ y-intercept:_______ y = 4/5x – 2 4/5 -2

In General Ax + By = C y = -a x + c b b m = -a/b y-intercept = c/b

TOO Identify slope and y-intercept: 5x + 2y = 12 -5x -5x y = -5/2x + 6 2 2 2 y = -5/2x + 6 Slope:______ y-intercept:_______ y = -5/2x + 6 -5/2 6

Homework Equations in Two Variables (pt. 1) Show your work at the bottom of the paper Convert to y=mx + b State m and b