Please show how I can use excel solver to solve for T in this problem:

Calculate the adiabatic temperature of the combustion products if methane is burned with 20% excess oxygen for the following 2 cases. In each case the reactants enter at 25 ^oC

1- Methane is burned with pure oxygen

2- Methane is burned with air. For the purposes of this problem air is 21% oxygen and 79% nitrogren.