please help me and show all your work please

Answer:
(3/12) or (1/4) of the bread was used for the recipe
Step-by-step explanation:
(7/12)+(2/12)=(9/12)
(12/12)-(9/12)=(3/12)
Equation?
(12/12)= x + (9/12)
x is the amount of bread used in the recipe, also sorry if it's not helpful...