Draw a diagram showing points \(A(-3,1)\), \(B(4,2)\), \(C(9,-3)\), \(D(2,-4)\).

- For the figure \(ABCD\) state and prove a fact (or facts) sufficient to ensure that it is a parallelogram.

What facts do you know about a parallelogram? Which of these facts show that \(ABCD\) is definitely a parallelogram? Can we prove one of these facts here?

- Prove that \(ABCD\) is not a square.

Which properties of a square are not met by every parallelogram? Could we show that one of these square properties is not met by this parallelogram?