From your description, you are not dealing with a parallelogram but rather a trapezoid. In a parallelogram, the top is parallel to the bottom, and the two sides are also parallel.
By "d2" do you mean "d squared"? (Online, d^2 = d squared.) Is there supposed to be an equal sign anywhere in your "Continuation"?
Repost your questions in clearer terms.
A parallelogram has a 7-inch side and a 9-inch side, and the longer diagonal is 14 inches long. Find the length of the other diagonal. Do you need your calculator to do it?
then, (Continuation) Evaluate 72 + 92 + 72 + 92 − 142 − d2, where d is the length of the shorter diagonal.
3 answers
What is the perimeter of a triangle whose sides measure 15cm, 17cm, and 10cm?
Find the side of a square whose diagonal is 16√2 cm.
1 answer