I need some help with setting up an excel sheet for the following formula. It's a calculation for Viscosity. A viscosity cup is used to determine T1. The time T1 is the time it takes for the viscosity cup to empty.
T1 is the Time as per ISO 4mm Cup

Calculate CSt from:
CSt=(1.37* T1)- (200/T1)
Calculate T2 from:
CSt= (4.57*T2)-(452/T2)
The time T2 is the time as per Din 4 mm
Cup. The Specification is 0 to 70 seconds as per
the 4mm Din Standard. Cst (Centistokes) is the unit of measure for viscosity. When I input a value for T1 using the formula then the quadratic equation will be solved and I will have the solution for T2. Any help would be appreciated.