Answer
F=1+1/2
Explanation:
(10)=-2F+13
We move all terms to the left:
(10)-(-2F+13)=0
We get rid of parentheses
2F-13+10=0
We add all the numbers together, and all the variables
2F-3=0
We move all terms containing F to the left, all other terms to the right
2F=3
F=3/2