Answer:
it's = 0
you have to use the steps of maths
I think the question is
Find the value of c so that (x-5) is a factor of the polynomial

The other factor is going to be some quadratic. We can say a few things about its coefficients but let's start by saying in general it's



Equating respective coefficients,




so we get



Answer: -37
Check:

166.7 may be the answer but the question is very confusing
(5,12,13) is a right triangle and can be constructed.
All the others do not satisfy the triangle inequality, i.e. the sum of two short sides must exceed the long side in order for the triangle to be constructed.
Examples:
2+11<15, so no
3+7<11, so no
4+8<15, so no
but 5+12>13 so yes, it can be constructed.
√16=4
Hope i could help. -\(-_-)/-