I'm stuck on this question completely, wondernig if you can help me out.
"The cake is designed in the shape of two touching circles with two tangents to the outer circles. The circles touch at the origin, whilst the tangents meet the y axis at (0,6).
The outer circle interesects the y axis at (0,4).
The equation of the inner circle is given by x^2+y^2-3y = 0 (^2 = squared).
Find the total "length" of the icing needed to decorate the cake (ignore thickness)."
It's a 9 mark question and I have no idea where to start