Depending on the kind of project that you have in mind you can use symbolic mathematics program to gather flexibility.
Here an example with sympy
and a live shell to test it without installations.
from sympy import symbols, Eq, solve
# declare the symbols
x, a, b = symbols('x a b')
# set up the equation
eq = Eq((1.1*x)+(b+(b*0.1)), a)
# solve it (for hard ones there are several types of solvers)
sol = solve(eq, x)
# fix the free variables
extra_pars = {a.name: input('a:'), b.name: input('b')}
# replace into the expression
new_sol = sol[0].subs(extra_pars)
print(new_sol)