They didn't make it easy. Grid lines are apparently 3 apart, but the offered coordinates are all multiples of 4. It appears the only point that is in the doubly-shaded area is ...
... B (-4, -10)
To solve for x just isolate x by moving the other variables so....:
First add c to both sides
g+c= y+x
Subtract y from both sides
g+c-y= x
That should be your final answer (we cannot come up with an actual digit for x because there are no numbers in this equation we simply can make an equation for x)
Answer:
0
Step-by-step explanation: