The combined gas law relates the variables pressure, temperature, and volume whereas the ideal gas law relates these three including the number of moles.
The equation for the ideal gas law is PV/T = k
P represents pressure, V represents volume, T temperature in kelvin
k is a constant.
The ideal gas PV= nRT
Where P,V,T represent the same variables as in the combined gas law. The new variable, represents the number of moles.
R is the universal gas constant which is
0.0821 (Liters x atmospheres/mol x Kelvin).
You can rewrite equation as PV/nT =R