One endpoint of a line segment is at (1, 2). the line is bisected by placing the midpoint of the line segment at (5, 8). what are the coordinates of the other endpoint?

 The midpoint of a line segment is (-1,-3). One endpoint is (7,3). What is the other endpoint? ... Since we are trying to find the coordinates of the second endpoint, (x2,y2), let's ... And since y = -3 and y1 = 3, we get y2 = 2*(-3) - 3 = -9. ... The line is bisected by placing the midpoint of the line segment at (7, 8).