Answer:
a = ( d-c)/b
Step-by-step explanation:
to solve for a in this expression , ab + c = d , you are going to try and express a in terms of b,c and d.
to do that
ab + c = d
ab = d-c
divide both sides by the coefficient of a which is b
ab/b = d - c/b
a = ( d-c)/b
