<span>A line segment has (x1, y1)as one endpoint and (xm, ym)as its midpoint.
Use the formula? (x2, y2) = (2xm − x1, 2ym − y1)
to find the coordinates of the endpoint of a line segment if the coordinates of the other endpoint and midpoint are (1, 8), (−3, −1) and (−7, 16), (3, 6),respectively.
Let y = the length of the 3rd side x+3 + 2x+4 + y = 6x x + 2x + 3 + 4 + y = 6x 3x + 7 +y = 6x 7 + y = 3x y = 3x - 7 The length of the third side in terms of x is 3x-7