// triangle-parallel-are-collinear-ex134.ggb 0.22s 0.15s 0.13s, 0.09s, 0.06s
// [v8^2*v6-v8*v6^2+v6^2*v4-v6*v4^2,v8*v5-v7*v6-v5*v4+v6*v3,v8*v7*v6-v7*v6^2+v6^2*v3-v6*v4*v3,v8*v6*v4-v6*v4^2,v8*v6*v3-v6*v4*v3,v5^2*v7-v5*v7^2-v5^2*v3+v5*v3^2,v5*v7*v6-v7^2*v6-v5*v6*v3+v6*v3^2,v5*v7*v4-v5*v4*v3,v5*v7*v3-v5*v3^2,v7*v6*v4-v6*v4*v3,v7*v6*v3-v6*v3^2]
aa:=eliminate([-1*v9*v8+v10*v7,-1*v9*v6+v10*v5+v9*v4+-1*v5*v4+-1*v10*v3+v6*v3,v11+-1*v9+-1*v7+v3,v12+-1*v10+-1*v8+v4,v13*v12+-1*v14*v11+-1*v13*v10+v11*v10+v14*v9+-1*v12*v9,v13*v6+-1*v14*v5,v15+-1*v9+-1*v7+v5,v16+-1*v10+-1*v8+v6,v17*v16+-1*v18*v15+-1*v17*v10+v15*v10+v18*v9+-1*v16*v9,-1*v17*v4+v18*v3,v19+-1*v9+v5,v20+-1*v10+v6,v21*v20+-1*v22*v19+-1*v21*v10+v19*v10+v22*v9+-1*v20*v9,-1*v21*v8+v22*v7+v21*v4+-1*v7*v4+-1*v22*v3+v8*v3,-1+-1*v28*v21*v18+v28*v22*v17+v28*v21*v14+-1*v28*v17*v14+-1*v28*v22*v13+v28*v18*v13],revlist([v9,v10,v11,v12,v13,v14,v15,v16,v17,v18,v19,v20,v21,v22,v28]))