Answer:
Part A: 2D + 3 = A
Note: I have likely given you the answer to the whole problem. See below.
Explanation:
Givens
- Alan = A
- Bruce = B
- Cecil = C
- Dylan = D
Comment
You have to pay the most attention to Alan and Bruce. Once you have equations for those two. Cecil's weight is just the sum of those two.
Alan
Alan = Twice*Dylan + 3 or
A = 2*D + 3
Bruce
Bruce = three * Dylan - 12
B = 3*D - 12
Cecil
Cecil = Alan + Bruce
C = A + B
Note
The last equation shows you how to combine the first two.
C = A + B
A = 2D + 3
B = 3D - 12
C = 2D + 3 + 3D - 12
C = 5D - 9