Age 14 to 16 Challenge Level:
Try drawing a rectangle around the parallelogram. If
you can work out the area of the rectangle and the areas of the
parts of the rectangle outside the parallelogram, then you should
be able to find the area of the parallelogram.
Don't forget that you can break up complicated shapes into simpler
small shapes (such as triangles and rectangles) whose areas are
easier to find.