We have the following:

solving for x

The solution of x is equal to 28, therefore 12 is not a solution of the equation
Answer: I'm pretty sure that it´s C but Im not sure.
Sorry if that's wrong.
Given:
Total number of pieces: 117
watch = x
earrings = four times as many earring as watches = 4x
necklaces = half the number of necklaces as earrings = 1/2 * 4x = 2x
bracelets = necklaces = 2x
x + 4x + 2x + 2x = 117
9x = 117
x = 117/9
x = 13
watches: x = 13
earrings: 4x = 4(13) = 52
necklaces: 2x = 2(13) = 26
bracelets: 2x = 2(13) = 26
13 + 52 + 26 + 26 = 117
There are 13 watches, 52 earrings, 26 necklaces, and 26 bracelets.
What's the problem about geometry? Which section?