I'm trying to solve a set of equations with SymPy 0.7.1:

from sympy import *
equations = [
    Eq(S('vf'), S('vi + a*t')),
    Eq(S('d'), S('vi*t + 1/2*a*t**2')),
    Eq(S('a'), S('10')),
    Eq(S('d'), S('60')),
    Eq(S('vi'), S('5'))
]
print solve(equations)

produces the correct result, but in a strange order:

[(-4, 10, 60, -35, 5), (3, 10, 60, 35, 5)]

How can I identify which value fits which variable? The variable order seems arbitrary. The documentation suggests providing additional arguments:

print solve(equations, var('a'), var('d'), var('t'), var('vi'), var('vf'))

But this seems to have no effect.

Thanks in advance for any help!

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