Linear nonhomogeneous simultaneous equations

Write a program in BASIC for solving linear nonhomogeneous simultaneous equations by... 

What we fomierly called the nonhomogeneous vector (Chapter 2) is zero in the pair of simultaneous nomial equations Eq. set (6-38). When this vector vanishes, the pair is homogeneous. Let us try to construct a simple set of linearly independent homogeneous simultaneous equations. 

All the tanks are at an initial temperature of 20°C. Find the time it will take for the third tank to reach 99% of its steady state value. The values of the constants are W = 100 kg/min, M = 1000 kg, Cp = 2kJ/kg°C, and UA = 10kJ/min°C. Determine how this time varies with the parameters a and p. Equations (equation (2.17)) can be solved using Maple and the procedure described above for nonhomogeneous simultaneous linear ODEs follows. 

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