How can we solve ax + z = aw - y for a

ax + z = aw - y

ax - aw + z = - y Subtract aw from both sides.

ax - aw = - y - z Subtract z from both sides.

a (x - w) = - y - z Factor ax - aw.

a = (-z - y) / (x - w) Divide x - w froem both sides.

a = (-1 (y + z)) / (x - w) Change the solution.

a = - (y + z) / (x - w)