Question 738125
The lefthand member is a plainly expressed whole number.  The righthand member is a variable which has been shown as combined with another plainly shown whole number.  We want to isolate the variable number.  We do this using the additive inverse of -25.  The additive inverse of -25 is +25.


Add +25 to the lefthand member and to the righthand member of the equation and simplify.  You now have solved for b.