Answer:


Step-by-step explanation:
(1) Making x the subject:

To make x the subject of original expression, we send the x to the left side of expression and all of the other components to the right side of expression.
The detail procedure is described as following:

Apply associate property:
<=>

Send 4y to the right side (the sign of 4y must be changed from positive to negative):
<=>

Divide both sides by 4:
<=>

(2) Make b the subject:
, applying the similar procedure in part (1):

Send
to the right side (the sign of
<=>

Divide both sides by
:
<=>

Hope this helps!
:)