Simultaneous Equations - How many solutions - Extension

This task is to help determine student’s understanding of how many solutions a pair of simultaneous equations would have. I did this with an extended Grade 6 (UK year 7) class and it took us around 40 -45 minutes where I left them to work on the “starter” for 10-15 mins on their own.
I am considering making this into an investigation/ a B crtierion assessment for the MYP
To get the most out of it, students should be secure in being able to solve the simultaneous equations (using substitution, elimination AND graphs), be comfortable with the idea of plotting graphs (preferably by using y = mx +c) and understanding what equations would be parallel lines.