WolframAlpha computational knowledge AI
solve{-1.1a1+3.8a2+7.2a3-2.1a4=3.5, 0.1a1+0.2a2+5.4a4=2.9, 7.6a1+2.8a2-1.4a3+3.2a4=11.1, 0.6a1+7.9a2+2.3a3+7.4a4=-2}