Line Equations:
Slope of the line through points P1(x1, y1) and P2(x2, y2):
Point-slope equation of the line through
point P1(x1, y1) with slope m: y – y1 = m(x – x1)
slope m and y-intercept b: y = mx + b
Two-intercept equation of the line with
x-intercept = a and y-intercept = b: