Solving for different letters, a, b?

Question

solving for 'a'?

BA + C = D

1. A = D - B - C

2. A = (D - C)/B

3. A = (C - D)/B

NOW, SOLVING FOR B

A = 3(B + C)

1. B = (A - C)/3

2. B = (3A - C)/3

3. B = (A - 3C)/3

Answer 1

1st problem:

BA + C = D

BA = D - C

A = (D - C)/B

Answer: 2. (D - C)/B

2nd problem:

A = 3(B + C)

B + C = 1/3A

B = 1/3A - C

B = (A - 3C)/3

Answer: 3. B = (A - 3C)/3

Answer 2

the first one is 2. A = (D - C)/B

the next one is 3. B = (A - 3C)/3

Answer 3

BA + C = D

BA = D - C

A = (D - C) / B

ANSWER: 2

A = 3(B + C)

A = 3B + C

3B = A - C

B = (A - C) / 3

ANSWER: 1