Answer:
(a).y=5z+x
this isn't a problem, just flip x to the other side
so x = 5z-y
(b). b=x/2a
cross multiply
x = b×2a
x= 2ab
c.8d=cx
divide both sides by c
8d/c=cx/c
x=8d/c
d.3px=12q
divide both sides by 3p
3px/3p=12q/3p
x=12p/3q
e. 4x=m/3-n
cross multiply
4x × 3 = m-n
12x = m-n
divide both sides by 12
12x/12=m-n/12
x = m-n/12
