# Thread: Paralellogram Unnsovlable Zeroes!

1. ## Paralellogram Unnsovlable Zeroes!

Here is the question in hand:

The problem is, I try using the cross product and I get zero.

Let the first point be A, second be B, third be C and fourth be D;

ad - bc = 0

So how do I solve this?

0 is not an accepted answer.

2. Originally Posted by JoeyCC
Here is the question in hand:

The problem is, I try using the cross product and I get zero.

Let the first point be A, second be B, third be C and fourth be D;

ad - bc = 0

So how do I solve this?

0 is not an accepted answer.
Let $u = \vec{CD}$ and $v = \vec{AC}$ with the third compenent of each to be zero, then cross them and take the magnitude.

3. The cross product has three different zero componenets. It does not work.

4. Originally Posted by JoeyCC
The cross product has three different zero componenets. It does not work.
Show us what you did.