Help! I got 7 but it told me it was wrong?

Answer:
-7
Step-by-step explanation:
it is -7 you have to get X by yourself
3 = 10 + x
subtract 10 from each side
x = -7
Answer: -7
Step-by-step explanation:
10+x=3 subtract 10 from both sides, to isolate x
x=3-10
x= -7
Hope this helps!