WRITING+EQUATIONS+OF+LINES

When an equation is in slope intercept form m= the slope and b= the y intercept.

There are 3 types of linear equations:

1. Standard: Ax+By=C

2. Slope Intercept: y=mx+b

3. Point Slope: y - y1 = m( x- x1)

If you are given two points on the line first determine the slope, then put one of the points and the slope into point slope form. Example: (3,4) and (2,3) Slope = 1 Point slope: y-4=1(x-3) Solve and put into either standard form or slope intercept form.

If 2 lines are parallel the slopes are equal and if 2 lines are perpendicular the slopes are opposite reciprocal. Example: A line parallel to y = 3x through ( 5, 10) Slope: 3 Point Slope: y - 10 = 3( x - 5) Solve and put into standard form or slope intercept form.

Example: A line perpendicular to y = 3x - 6 with same y intercept. Slope: 3 Opposite reciprocal: -1/3 Solve and put into standard form or slope intercept form.