Answer:
2d(b-c)+b=a
Explanation:
First you start off with the equation given
2d=(a-b)/(b-c)
Second, you want to start getting A by its self so that means you have to multiply both sides by (b-c) to get (a-b) by its self. (underlined portion cancles out)
2d(b-c)=((a-b)/(b-c)) (b-c) ----> 2d(b-c)=a-b
Finally, you want to add b to both sides to get a completely by it's self. (underlined portion cancles out)
2d(b-c)+b=a-b+b -----> 2d(b-c)+b=a