Put in the given numbers and you have two equations in two unknowns. .. 10Ta +25Tb = 220 .. Ta +Tb = 10
It is convenient to solve this by substitution. Use the second equation to write an expression for Tb. .. Tb = 10 -Ta Now use this in the first equation. .. 10Ta +25(10 -Ta) = 220 .. -15Ta +250 = 220 . . . . . . . collect terms .. -15Ta = -30 . . . . . . . . . . . . . subtract 250 .. Ta = 2 . . . . . . . . . . . . . . . . . divide by the coefficient of Ta .. Tb = 10 -2 = 8
