Find all points on the xaxis that are 4 units from the midpo
     Find all points on the x-axis that are 4 units from the midpoint of the line segment joining (3, 4) and (-3, - 10)  (x, y) =  (smaller x-value)  (x, y) =  (larger x-value)  
  
  Solution
midpoint of (3, 4) and ( -3, -10) = (0, -3)
Lets assume apoint on x axis be ( x, 0)
Distance between (0, -3) and (x,0) = sqrt( (-3)^2 + x^2
sqrt( (-3)^2 + x^2) = 4 units
Taking square on both sides:
9 +x^2 = 16
x^2 = 7
x = +/-sqrt7
The points are ( sqrt7 , 0) and (-sqrt7 , 0)

