1. 2.3 Equations of Lines Going the other direction – from a picture to the equation

2. There are 3 standard forms of equations 1.Slope intercept form y = mx + b 2.Standard form Ax + By = C A, B and C are integers and A is positive slope y intercept

3. There are 3 standard forms of equations 3. Point-Slope form (the new one) I like this form – lets see why!! (this is fine for finding answers, but it isn’t simplified as is)

4. So, what do you need to have to find the equation of the line? Slope anda point

5. How can I be given slope? 1.The slope is…. 2.The line is parallel to… 3.The line is perpendicular to…. 4.The line passes through the points….

6. How can I be given a point? 1.The point is…. 2.The line passes through the point… 3.The line passes through the midpoint of.. 4.The line passes through the point of intersection of the lines…. 5.The line passes through the x/y intercept of the line….

7. Lets try some problems. 1.Convert y = 1.5 x – 6 to standard form. 2.Convert 10x – 2y = 3 to slope/intercept form. Find the equation of the line that has 3.Slope = 3, y intercept = 10 4.Slope = 3, x intercept = 10 5.Slope = 3, passes through (10, 10)

8. Lets try some problems. 6.Parallel to 2x + 3y = 7 and passes through (-1, -1) 7.Perpendicular to 4x – y = 7 and passes through (-1, -1) 8.Perpendicular to y = 3 and passes through (12, 4) 9.Parallel to x + 2y = 1 and passes through the point of intersection of the lines y = 3x – 2 and y = 2x + 1.