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# Differentiation help!!!!!!! watch

1. A wire is bent into shape ABCDE. ABDE is a rectangle and BCD is a semicircle with diameter BD. The area of the region enclosed is R m^2. AE = x metres and and AB = ED = y metres. The total lennth of the wire is 2m

a) Find an expression fo y in terms of x.

Ive sketched it and put:

Perimeter = x + y + (2TTr)/2 = 2

Perimeter = x + y + (2TTx/2)/2 = 2

The answer says: y = 1 - x/2 = TTx/4

How do you get to that?!

Thanks for any help.
2. x + 2y + pi*x/2 = 2 - don't forget to include both sides AB and DE. Rearrange for y.

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