Question

(l-b)square=(l+b)square-4lb
Which formula of quadrilateral is this?
I just want its name,,,,plse its urgent its my EXAMS

Answer 1

33625:

Task. (l-b)square=(l+b)square-4lb

Which formula of quadrilateral is this?

I just want its name,,,plse its urgent its my EXAMS

Solution. This formula does not specify the special type of quadrilateral because if you open the brackets and simplify expressions you will get identity. Perhaps you mean parallelogram law $2(x,x) + 2(y,y) = (x + y,x + y) + (x - y,x - y)$ for Hilbert spaces. Then quadrilateral is parallelogram.