if the following are true:

• a = b + c
• c = d

then b + d = a

Start from the conclusion and work back up the proof. Click the arrow to show the parents.

• b + d = a,

  if the following are true:

  • a + b = c
  • b = d

  then a + d = c

  • c = d
  • b + c = a,

    if a = b, then b = a

    • a = b + c