Answer:
11+x because the equation is reversabel.
Step-by-step explanation:
Do 13 x 13 x 13.
13 x 13 x 13 = 2197 in3
Hope this helps!
B hope it helps SORRY IF IM WRONG
The meaning of the question is
Let the unknown number be x
Therefore x+7=16-2x
Now 2x+x=16-7
3x=9
X=9/3
x=3