kourousafama,

Please post one question per thread.

These questions are already explained in this forum.You can search it.If you still have doubts,please post it.

Hi,

I have searched the forum for answers to these questions but I haven't found them all. Apart from the fact that this is very much time consuming, some of the explanations don't appear very clearly, and there are sometimes discussions among members etc.

Could anybody provide a clear answers to these questions or redirect me to the exact post within this forum?

As I don't have much time left for practice, this would be really much appreciated!

Many thanks,

Q1: Note that if the isosceles triangle is right angled, then the angles are 45-45-90.
Thus the sides will be in the ratio 1:1:sq root 2.
This can also be written as sq root 2 : sq root 2 : 2 (Multiplying all the sides with sq root 2).

Thus the perimeter becomes 2 + 2 sq root 2 --> This is of the form given in the question.
The hypotenuse for this triangle is 2.
So, now tell me what would be the hypotenuse of the triangle in the question?

Q2: One part of the wire is used to make a circle of radius r. Thus the amount of wire that has been used is equal to the circumference of the wire. This is equal to 2*pi*r.

So remaining wire 40 - 2*pi*r
This is the perimeter of the square.
So one side of the square will be 10 - 1/2*pi*r.

Now you know why the last answer is correct.