16x=10(x+1)=26(+1)-16

The solution to the first pair of equal expressions is:

16x = 10(x + 1)

16x = 10x + 10

6x = 10

x = 10/6 = 1 and 2/3


The solution to the second pair of equal expressions is:

10(x + 1) = 26(+1) - 16

The left side is 10(x + 1) = 10x + 10

The right side is  26(+1) - 16 = 26-16 = 10

The equation now says    10x + 10 = 10

Subtract 10 from each side:   10x = 0

The solution to this pair of equal expressions is   x = 0 .

I think I understand the weird question now.  It's trying to say that
the first expression is equal to both the second and third expressions.
Let's try the first and the third:

16x = 26(+1) - 16

16x = 26 - 16

16x = 10

x = 10/16 = 5/8 = 0.625

Nope, that wasn't it.

The upshot of all my research is:  I have no idea what the question is trying to say,
therefore no clue of what the actual question is, and no direction toward an answer.

It is 12 because I say so bye