mathematics
posted by gail on .
Given the points A(1;1) ,B(2;5) ,C(1;5/2) and D(
X;4) andAB perpendicular to CD, determine the value of X

AB has slope (5(1))/(2(1)) = 2
CD has slope (5/2(4))/(x(1)) = (3/2)/(x+1) = 3/(2x+2)
So, we need to have
(2x+2)/3 = 2
x = 4