If p is the perimeter of rectangle X, what is the value of

Question

Hi Everyone!
Pls, help me to understand why an answer "A" doesn't work for the following problem

If p is the perimeter of rectangle X, 
what is the value of p?
 1. Each diagonal of X has a length of 5
 2. The area of X is 12

Why doesn't 3-4-5 rule aplicable here?

Thanks in advance

aaaqqq222 · Answer

Imagine a square with diagonals = 1 and some perimeter, than virtually make this square almost flat rectangle. Is perimeter seems the same? So knowing only diagonals you can't be sure about perimeter.

kostyan5 · Answer

3-4-5 rules doesn't apply because you only have the 5. You can only use 3-4-5 rules on a right triangle with two known sides.

gnothobiot · Answer

Thanks a lot! That's very clear a logical now

KarishmaB · Answer

3-4-5 is not the only way in which you get a 5 in the hypotenuse. But it is the only way in which all sides are integers with 5 as the hypotenuse. (Pythagorean triplets give you all integer sides.)

There are many other ways of getting 5 e.g.
1,  \sqrt{24} , 5
2,  \sqrt{21} , 5
etc

loser · Answer

Thanks for the explanation.

If p is the perimeter of rectangle X, what is the value of

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