$ 矩陣的列運算解線性方程式 $

s = 1.2 (slider from -5 to 5, step 0.1)
list_2 = Sequence(Random[-5, 4] + s * 0, k, 1, 12)
list_1 = Sequence(If[Element[list_2, i] ≟ 0, 5, Element[list_2, i]], i, 1, 12)
a1 = Element(list_1, 1)
b1 = Element(list_1, 2)
c1 = Element(list_1, 3)
d1 = Element(list_1, 4)
a2 = Element(list_1, 5)
b2 = Element(list_1, 6)
c2 = Element(list_1, 7)
a3 = Element(list_1, 9)
b3 = Element(list_1, 10)
c3 = Element(list_1, 11)
d3 = Element(list_1, 12)
d2 = Element(list_1, 8)
text1: "$ \left [\begin{array}{cc} " + (LaTeX[a1]) + " & " + (LaTeX[b1]) + " & " + (LaTeX[c1]) + "&" + (LaTeX[d1]) + " \\ " + (LaTeX[a2]) + " & " + (LaTeX[b2]) + " &" + (LaTeX[c2]) + "&" + (LaTeX[d2]) + "\\ " + (LaTeX[a3]) + " & " + (LaTeX[b3]) + " & " + (LaTeX[c3]) + "&" + (LaTeX[d3]) + "\\ \end{array}  \right ]  $"
Problem: "$ \left\lbrace\begin{array}{ll} " + (LaTeX[a1]) + "x" + (LaTeX[If[b1 < 0, "-", "+"]]) + "" + (LaTeX[abs(b1)]) + "y" + (LaTeX[If[c1 < 0, "-", "+"]]) + "" + (LaTeX[c1]) + "z=" + (LaTeX[d1]) + " \\ " + (LaTeX[a2]) + "x" + (LaTeX[If[b2 < 0, "-", "+"]]) + "" + (LaTeX[abs(b2)]) + "y" + (LaTeX[If[c2 < 0, "-", "+"]]) + "" + (LaTeX[abs(c2)]) + "z=" + (LaTeX[d2]) + " \\" + (LaTeX[a3]) + "x" + (LaTeX[If[b3 < 0, "-", "+"]]) + "" + (LaTeX[abs(b3)]) + "y" + (LaTeX[If[c3 < 0, "-", "+"]]) + "" + (LaTeX[abs(c3)]) + "z=" + (LaTeX[d3]) + " \end{array}   \right.\  $"