The coordinates of A is (7,11) and B is a point on the x-axis. Given that M is the midpoint of AB and the x-coordinate of M is 2, find the coordinates of B.
LET
A(7,11) M(2,t) B(r,0)
Since M is the midpoint
(7+r)/2=2
7+r=4
r=-3
So B is the point (-3,0)
