Write an equation perpendicular to the equation through the
     Write an equation perpendicular to the equation through the given point.  y + 2 = - 1/2(x - 4); (-5,17) 
  
  Solution
The slope of the given line is m1 = -1/2
To get the perpendicular slope we use m1 .m2 = -1
so , m2 = 2
So , equation of line passing through ( -5,17) as ( x1,y1) and slope 2 is
y - y1 = m2 ( x- x1)
y -17 = 2 ( x + 5)
y -17 = 2x + 10
y -2x = 27

