For question 8 on the tickbox #10 quick the question reads: Concentric circles π΄ and π΅ have radii of π₯ and π₯-3, respectively. If the area of the larger circle that is not covered by the smaller circle is 27 π, what is π₯?

When I attempted to solve I first transformed the relationship between the radii into x and x+3 since I felt like those values would be easier to work with. Then going through and subtracting the areas the pis and the x^2 terms cancel out and youβre left with 6x+9=27 which gives 3

What is confusing me is that in Gregβs solution when keeping the relationship as x and x-3 the equation becomes 6x-9=27 which yields 6.

I would have thought that transforming the relationship between the radii would not affect the answer but it appears as if either it does or I am missing something glaring when solving with x and x+3