A little help with some Murderous Maths question

[wyz135]

I was stuck at a question in one of my school assignment. Here's the question: Marco anchors his boat in water that is twelve meter deep, as shown in the diagram (At the bottom). So about how long, in metres, is the part of the anchor line that is under the wate.
My first thought is that it appeared like a quater of a circle and I tried to find the area, but later I then realise it look more like a oval shape. Soon I realise I'm trying to use integral calculus(Reading a thousand page maths book with calculus) on it to find the length, it only makes me more confuse. So I know many of you here are have more education then I do so please help me, I haven't even touch on calculus yet in school. Anyway million thanks:):):):)

[Mike]

It looks like an ellipse. Unless they give you a specific equation for the line made by the anchor, I'd go with the approximation formula for the circumference of an ellipse. Unless this is a calculus class, in which case you'll want to come up with an equation for the ellipse and use the integral method.

http://mathcentral.uregina.ca/QQ/database/QQ.09.99/proffit1.html

[wyz135]

MILLION THANKS for the site!! I manage to work it out to a around 18m. Thanks man:):):)