Can someone explain inverse operations to me?

Question

Our teacher was off today and I just want to understand.
So, I get simple stuff like adding and subtracting but, like, for example if we were to make x the subject in this example (m=yx)how were we to do it?
More example I don't understand:
Make x the subject:
Y=s²-y
Make p the subject
W=p/b - t
Please help me!

Answer 1

in m=yx
to "make x the subject" means to solve for x
so in yx, the x is multiplied by y, the inverse operation of multiplication is division, so ...

I will divide both sides of the equation by y
m = yx -----> m/y = yx/y
m/y = x <---- that's all there is to it!

in W=p/b - t
the last thing they did was to subtract t, so the first thing I will do to reverse the process is
to add t
W=p/b - t ------> W+t = p/b - t + t
W+t = p/b
p is divided by b, so I will do the inverse of division which is multiplication, then
(W+t)*b = p/b * b
b(W+t) = p , all done!

remember the inverse of addition is subtraction, the inverse of multiplication is division,
the inverse of taking the square root is squaring, etc.