Slope-Intercept and Point-Slope Forms of a Linear Equation

 y = mx + b ◦ m represents the SLOPE (rise/run) ◦ b represents the Y-INTERCEPT –> (0, b)

 1. y = -x x + y = 4  3. 16y = 8x x + 2y = 8

 Find where the line crosses the y-axis. This is the y-intercept, b.  Select 2 points on the line and COUNT for slope using Rise. This is m. Run  Plug m and b into y = mx + b

 1) 2x + 3y = 1 and y = -2 x  2) 8x + 2y = 10 and x – 7 = 4y  3) 5x – 6y = 18 and -6x + 5y = 10

 See graph paper

 1. Rearrange into slope-intercept form if needed.  2. Identify the y-intercept (0, b) and plot it.  3. Beginning at b, move Up and Down, then to the Right for the slope (Rise/Run).  4. Connect the points with a straight line.

 1. 2x + 3y = 6  2. -2x + 5y = 10

 Used to write the equation of a line when you are not given its graph.  y – y 1 = m(x – x 1 ) ◦ m represents the slope ◦ x 1 and y 1 represent coordinates from an point on the line ◦ Simply plug in the m, x 1, and y 1 – then rearrange into slope-intercept form

 1. Slope = 3, through (0, -1)  2. Slope = 2/3, through (3, 6)  3. Through (-6, -2) and (5, -3)  4. Through (3, 0) and (-3, 5)