63 + (* - 72) = 63
* - 72 = 63 - 63
* - 72 = 0
* = 72 + 0
* = 72
* + (9 - 9) = 15
* + 0 = 15
* = 15 - 0
* = 15
(* - 5) + 5 = 70
* - 5 = 70 - 5
* - 5 = 65
* = 65 + 5
* = 70
40 + 22 - * + 40 = 80;
62 - * + 40 = 80
- * + 62 + 40 = 80
- * + 102 = 80
- * = 80 - 102
- * = - 22
* = 22
63 + (* - 72) = 63
* - 72 = 63 - 63
* - 72 = 0
* = 72 + 0
* = 72
* + (9 - 9) = 15
* + 0 = 15
* = 15 - 0
* = 15
(* - 5) + 5 = 70
* - 5 = 70 - 5
* - 5 = 65
* = 65 + 5
* = 70
40 + 22 - * + 40 = 80;
62 - * + 40 = 80
- * + 62 + 40 = 80
- * + 102 = 80
- * = 80 - 102
- * = - 22
* = 22