u=x5u2=x10Usingthissubstitutiontheequationbecomes
2u2u4=0Thisdoesnâtfactorandsoweâllneedtousethequadraticformulaonit.Fromthequadraticformulathesolutionsare
u=1p334Now
inordertogetbacktoxâswearegoingtoneeddecimalsvaluesfortheseso
u=1+p334=1:68614u=1p334=1:18614Now
usingthesubstitutiontogetbacktoxâsgivesthefollowing
u=1:68614:x5=1:68614x=(1:68614)15=1:11014u=1:18614:x5=1:18614x=(1:18614)15=1:03473Wehadtouseacalculatortogetthefinalanswerforthese.ThisisoneofthereasonsthatyoudonâttendtoseetoomanyofthesedoneinanAlgebraclass.Theworkand/oranswerstendtobealittlemessy.©PaulDawkinsAlgebraâ132â