Question

Three of the vertices of parallelogram ABCD are given. Find the coordinates of point D. Show your method. A (-2,-3) B (4,-3) C (3,2) D(x,y) . .​

Answer 1

D(-1,-8)

Explanation:

See attached graph.

Plot the given points, then find the equation that links A and C and a second one to link C and B. Plot those lines (Black and Red). Find 2 equations for lines parallel (same slope, m) to these two lines. Adjust the value of the y-intercept, b, such that one line intersects point A and the other point D (the Green and Blue lines). Where those lines intersect will be the point D.

D (-1,-8)