Why are all three branches of goverment equally powerful? please answer question.

I am not sure that you really can say that all of the
three branches of government are equally powerful.  But if I had to argue that they
were, I would say that it is because each can sort of cancel out an action of the
other.

For example, the President can veto a law that
Congress has passed.  In turn, Congress can override the President's veto if it has
enough votes.

When it comes to the judicial branch, they
can say that a law passed by Congress or an action of the President in
unconstitutional.

In that way, each branch can cancel out
things the others do.  This, you can argue, makes them all
equal.