Answer:
A= -7
B= 12
C= -13
Explanation:
This is how I do it
A) Subtract 4 from each side, and when you do that you get 7=-t which makes the answer -7.
B) Add 8 to both sides and you get f=12.
C) Subtract 5 from each side, and when you do that you get -k=13 which makes the answer -13.
I hope this helps, and have a great day! :)
Also if you need more of an explanation I can help!