From 1 to 9, fill in the following formula () + () = (), () - () = (), () + ()=（ From 1 to 9, the number can not be repeated, each number can only appear once, fill in the following formula () + () = (), () - () = (), () + ()=（

From 1 to 9, fill in the following formula () + () = (), () - () = (), () + ()=（ From 1 to 9, the number can not be repeated, each number can only appear once, fill in the following formula () + () = (), () - () = (), () + ()=（

Wrong question!
1： Move the second equation () - () = () to () + () = (), that is, three adders,
2： From large to small, 9 is the largest, which must be a sum. Assuming 1 + 8, then 2, 3, 4, 5, 6, 7 will be left, and then 7 is the largest. Set 7 = 2 + 5 or 7 = 3 + 4, and 3, 4, 6 or 2, 5, 6 will not be left
Similarly, if 9 = 2 + 7, then 1, 3, 4, 5, 6 and 8 are left. If 8 = 3 + 5, then 1, 4 and 6 are not left
Suppose that 9 = 3 + 6, leaving 1, 2, 4, 5, 7 and 8. Set 8 = 1 + 7, and the remaining 2, 4 and 5 will not work
Suppose 9 = 4 + 5, leaving 1, 2, 3, 6, 7 and 8. Set 8 = 1 + 7 or 2 + 6, and leave 2, 3, 6 or 1, 3 and 7