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

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

So, what do you need to have to find the equation of the line? Slope and a point Lets try one: Slope=2 and the y-int = 5

Find the equation of the line that has points of (0,3) and (4,0) Slope = 3, x intercept = 10 Slope = 3, passes through (10, 10)

Parallel to -4x + 2y = 10 and passes through (-1, -1) 7. Parallel to x + 2y = 1 and passes through the point of intersection of the lines y = 3x – 2 and y = 2x + 1. Solve systems of equations to get point!

Other Review Items Altitude Median Perpendicular bisector MP

Triangle ABC has vertices A(-4,-2) L(2,8) G(6,2) Write the equation of AL Find the Slope:

Triangle ABC has vertices A(-4,-2) L(2,8) G(6,2) Find the equation of the perpendicular bisector of LG. Steps: Find MP of LG (avg x, avg y) Find the slope of LG and take neg reciprocal 3. Plug in MP to find b L G A

Triangle ABC has vertices A(-4,-2) L(2,8) G(6,2) Find the equation of the altitude to AG Steps: Find the slope of AG and take neg reciprocal 2. Plug in point L to find b L G A

Group Problem: Find the distance between (0,4) and (3,0):