You are going to consider how the warm-up problem was created. You will need to create a similar problem with a different set of four straight lines.

- How can you guarantee that your four lines will intersect to form a triangle where each point on the triangle has negative coordinates?
- How can you ensure that just one triangle is created with these conditions?
- How many approaches can you find to create a similar problem?
- Which of your approaches to this problem is the most effective?

Once you have completed this problem you may like to consider the questions below to extend your thinking:

You might like to try a graphical approach to this problem, perhaps using Desmos.