It will be 11v
If you rearrange it to 12v- v
Then it’ll look like 12v- 1v
Which equals 11v
I believe it is 3x+21 but i could be wrong :/ my explaination is -3 • -X would be +3x because it was distributed and -3 • -7 would be +21
I believe the answer to this is the third box
Hope this is what’s you where looking for
