The coordinates of the mid-point of the line segment joining the pointsP(0,−4) and B(8,0) are (20+8​,2−4+0​)=(4,−2) It is known that the slope (m) of a non-vertical line passing through the points (x1​,y1​) and (x2​,y2​) is given by m=x2​−x1​y2​−y1​​,x2​=x1​Therefore, the slope of the line passing through (0,0) and (4,–2) is4−0−2−0​=−42​=−21​ Hence, the required slope of the line is −21​