Fill in each of the boxes with the numbers 1 to 9 so that the three horizontal equations are true.

Each number is used once; no repetition is allowed.

The calculations are done from left to right (i.e., 7-2x3=15, not 1) and may involve only positive numbers (so 5-3-7=-5 is not allowed).

                               _     _     _     _
 _     _     _     _     _    | | - | | x | | = | |
| | x | | x | | = | | + | | + |_| + |_| + | | + |_|
|_| - |_| x |_| = |_| - |_|             - |_|