Answer:
f=2
Explanation:
0.3+0.5f-0.7
Move the varibale (0.5f) to the left-hand side and change it's sign to negative.
-0.5+0.3+-0.7
Move the constant to the right hand side and change it's sign
-0.5f=-0.7-0.3
Calulate the differnce
-0.5f=-1
divide both sides by -0.5
F=2