In Maxima, how can I solve this equation?

Question

In Maxima, how can I solve this equation? And actually I have 24 unknown value with lots of this kind of equation. How I can use Maxima to solve?

to know the unknown value: a, b, c, d

eq:[a*c=8,a*d=10,b*c=12,b*d=15,a+b=5,c+d=9];
solve(eq,[a,b,c,d]);

Answer 1

With four unknowns you have to have four equations. Ignore one set of equations and run:

sol1: solve([a*c=8,a*d=10,b*c=12,a+b=5],[a,b,c,d]);
              [[a = 2, b = 3, c = 4, d = 5]]

Then, ignore an other set of equations and run again:

sol2: solve([a*c=8,a*d=10,b*c=12,c+d=9],[a,b,c,d]);
              [[a = 2, b = 3, c = 4, d = 5]]

If the two results are the same, then your system is consistent and has solution sol1 ≡ sol2.