Colour by simultaneous equations with extension

As the title suggests, this is a colouring sheet for practising solving linear simultaneous equations. It contains all levels of questions; ones that you can simply add/takeaway, ones the require one equation multiplying, ones that require both equations multiplying and ones that require rearranging/ reordering. Unlike other maths colouring sheets, each sheet only requires three different colours and therefore requires fewer teacher supplies. Students solve the answers to the equations and colour based on their solution. Two solutions do not fit the pattern and students are encouraged to find their own questions that will fit the pattern allowing for stretch and challenge. The solution is the pattern displayed. The white spaces are where the solution does not fit the pattern.
All feedback gratefully accepted.