Question 1035738
you're not doing anything wrong.
the answer is x = 4.
your "possible" answers are x = 4 or x = 31.
x = 31 is not possible because then the length and width of the picture would be negative.
that means that x = 4 is your answer.
i answered this previously.
hopefully you received that answer.
if not, let me know and i'll send it again.