3.5 is the answer to this problem
Answer: 
============================================
Work Shown:

---------------
Explanation:
The idea is to first get all the y terms to one side. I did this by subtracting 2y from both sides in the third step.
Then factor out y and divide both sides by (8x-2)
Afterward there's the optional steps of simplifying (as shown in the final two steps).
Answer: Quadratic; 6x^2, x, -12
Detailed Explanation:
The highest power of the function (degree) is 2. Therefore it is a quadratic function. The quadratic term is 6x^2 since its power is 2, the linear term is x since its power is 1 and the constant term is -12.
Rosie has more than 3 charms because she already had some charms
1. Factor out 9a^2 from the expression
9a^2 x(9x+y) - 90bx - 10by
2. Factor out -10b from the expression
9a^2 x(9x+y) - 10b x(9x+y)
3. Factor out 9x + y from the expression
(9x+y)x(9a^2 - 10b)
Solution: (9x+y)x(9a^2 - 10b)