You need to add 17.
x+-9=8
Add nine to each side
x+-9=8
+9 +9
-9+9=0 so nine cancels out.
8+9=17 so now you have:
x=17
Now you have the value of x.
- 8 + 17 = 9 =========
9
You need to add 6 - (-9) = 6 + 9 = 15.
you need to add +9 +9-7 = +2
You need to add 18 to negative 8 to get 10.
you need to add 10
17
9
It is: -9+16 = 7
10 - (-9) = 19
-9 + 11 = 2
1-9