Here's another solution, noticing that there are *two* yellow flowers in the third equation: Maxima 5.28.0-2 http://maxima.sourceforge.net using Lisp GNU Common Lisp (GCL) GCL 2.6.8 (a.k.a. GCL) Distributed under the GNU Public License. See the file COPYING. Dedicated to the memory of William Schelter. The function bug_report() provides bug reporting information. (%i1) r+r+r=60; (%o1) 3 r = 60 (%i2) r+b+b=30; (%o2) r + 2 b = 30 (%i3) b-2*y=3; (%o3) b - 2 y = 3 (%i4) solve([%o1,%o2,%o3],[r,b,y]); (%o4) [[r = 20, b = 5, y = 1]] (%i5) y+r*b,r=20,b=5,y=1; (%o5) 101 (%i6)