What is the mean absolute deviation of 28 30 28 39 25

Which of the following lines does not intersect the line y=-2x+3 ? a) y=2x b) y=2x-3 c) y=2x+3 d) y=-2x-3

Can someone me and do the problem plz so i can understand it more better

The diagonals of a quadrilaretral intersect at (-1,4). one of the sides of the quadrilateral is bounded by (2,7) and (-3,5) determine the coordinates of the other side in order for the quadrilaretral to be a square.