Hi Caramel17,

You know the midpoint ofACis(4, 3).Let's call that pointM.

You found the slope of the perpendicular which passes through

pointsBandD.

That would be3.

Using the slope of3and the midpointM(4, 3)and an endpointB(x, y),we get:

Equating the numerators and denominators, we arrive at:

You can find the coordinates of D in a similar fashion.

Let coordinates ofDbe