Gcse maths question

Hi, please could I have help on part b of this question? It says to draw suitable line but from what I have worked out, I should draw y=x^2-3x to get the solution for the equation but the markscheme says to draw y=2x-1? Please could some explain this? Thanks!!

You really want to get rid of the x^2 term, since you want to end up with a straight line (i.e. no powers of x greater than 1).

Notice that if $x^2-7x+4=0$, for example, then you could multiply the whole equation by 2, and get $2x^2-14x+8=0$ - it's the same function/graph.

Can you do something similar here, to start?