If the line l1 passses the point (5,x) and (-1,3) and l2 contains the points (x,6) and (2,0) ,then what is the value of x for which the two are perpendicular ?
slope of first = (3 -x) / (-1-5) = (x-3)/ 6 = m1
slope of second = (0-6) / (2-x) = 6 / (x-2) = m2
if perpendicular
m2 = -1/m1
6/(x-2) = -1 * 6/ (x-3)
-1 =(x-3) / (x-2)
-x + 2 = x - 3
2 x = 5
x = 2.5