Answer:
Just practice ,know different ways of solving it ,gain experince ,be smart and skilled.
Step-by-step explanation:
if you want to prove anuthing then go with the concept accoeding to the nature of the problem and there are almost many ways to prove anything so don't waste your time on way get on to the other ways.
It may not get proved at first time so keep on doing questions and when you have gained experience you know every nature of problems and then you are skilled properly.
Answer:
Definitely Option A.
When you expand the bracket of Option A... You have your equation
Which is
-1/4x + 1/2.