A regra de Cramer é uma das maneiras de resolver um sistema linear:
[tex]D \left[\begin{array}{ccc}4&-4&3\\2&1&2\\5&2&-2\end{array}\right] = -83
Dx \left[\begin{array}{ccc}7&-4&3\\15&1&2\\15&2&-2\end{array}\right] = -83
Dy \left[\begin{array}{ccc}4&7&3\\2&15&2\\5&1&-2\end{array}\right] = -249
Dz \left[\begin{array}{ccc}4&-4&7\\2&1&15\\5&2&1\end{array}\right] = -415
x=Dx/D =1
y=Dy/D=3
z=Dz/D=5
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