Question

Solve by cramers rule
X+3y+6z=2
3x-y+4z=9
X-4y+2z=7

Answer 1

∆ = \begin{pmatrix}1&3&6\\3&-1&4\\1&-4&2\end{pmatrix} = -58

X = (1/∆) = \begin{pmatrix}2&3&6\\9&-1&4\\7&-4&2\end{pmatrix} = -116/-58 = 2

Y = (1/∆) = \begin{pmatrix}1&2&6\\3&9&4\\1&7&2\end{pmatrix} = 58/-58 = -1

Z = (1/∆) = \begin{pmatrix}1&3&2\\3&-1&9\\1&-4&7\end{pmatrix} = -29/-58 = 0.5

Hence, x = 2, y = -1, z = -0.5.