I will medal and fan anyone who answers this:
there is an isocelles triangle the base is s and the other sides are r. one of the angles is 45 the others are 67.5
Prove that s^2 = r^2 (2-sqrt2)

Question

I will medal and fan anyone who answers this: 
there is an isocelles triangle the base is s and the other sides are r. one of the angles is 45 the others are 67.5 
Prove that s^2 = r^2 (2-sqrt2)

anonymous · Answer

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anonymous · Answer

this triangle is part of an octagon and teh octagon is inside a circle

anonymous · Answer

but the triangle is the main part i gues

anonymous · Answer

Yes, I don't think we need the other geometric info to figure this out. Have you tried the law of sines?

anonymous · Answer

yes but to no avail but it might work im not sure

anonymous · Answer

$$\frac{\sin67.5^\circ}{r}=\frac{\sin45^\circ}{s}$$
This identity will help later on:
$$\sin^2x=\frac{1-\cos2x}{2}$$

anonymous · Answer

okay but how?

anonymous · Answer

Replace any expressions with values you know (i.e. $\sin45^\circ$). Then square both sides.

anonymous · Answer

^Not the only way to do it, just a suggestion.

anonymous · Answer

i tried but could not do it pls help

anonymous · Answer

@SithsAndGiggles pls help!!