25d-14d+8d=95
as all of the terms on the left are 'd's then we consider them to be called like terms. When we have like terms we can add or subtract freely.
so:
25d-14d= 11d
11d+8d = 19d
therefore we get:
19d = 95
this is the same as
19*d=95
to find do we need to 'work backwards' to move the 19 to be with 95.
So to 'work backwards' we do the opposite of multiply and divide it instead to both sides of the equation.
19/19*d=95/19
d=95/19
d= 5