Réitigh {l}{x_{1}-x_{2}+x_{3}=2}{x_{1}+2x_{2}=1}{x_{1}-x_{3}=4}

$$\left\{ \begin{array}{l}{ x _ { 1 } - x _ { 2 } + x _ { 3 } = 2 }\\{ x _ { 1 } + 2 x _ { 2 } = 1 }\\{ x _ { 1 } - x _ { 3 } = 4 }\end{array} \right.$$

Réitigh do x_1,x_2,x_3.

$$x_{1} = \frac{13}{5} = 2\frac{3}{5} = 2.6$$

$$x_{2}=-\frac{4}{5}=-0.8$$

$$x_{3} = -\frac{7}{5} = -1\frac{2}{5} = -1.4$$

Céimeanna gearra ag baint úsáid as ionadú

Réitigh x_{1}-x_{2}+x_{3}=2 do x_{1}.

$$x_{1}=x_{2}-x_{3}+2$$

Cuir x_{2}-x_{3}+2 in ionad x_{1} sa dara agus sa tríú cothromóid.

$$x_{2}-x_{3}+2+2x_{2}=1 x_{2}-x_{3}+2-x_{3}=4$$

Réitigh na cothromóidí seo do x_{2} agus x_{3} faoi seach.

$$x_{2}=-\frac{1}{3}+\frac{1}{3}x_{3} x_{3}=-1+\frac{1}{2}x_{2}$$

Cuir -\frac{1}{3}+\frac{1}{3}x_{3} in ionad x_{2} sa chothromóid x_{3}=-1+\frac{1}{2}x_{2}.

$$x_{3}=-1+\frac{1}{2}\left(-\frac{1}{3}+\frac{1}{3}x_{3}\right)$$

Réitigh x_{3}=-1+\frac{1}{2}\left(-\frac{1}{3}+\frac{1}{3}x_{3}\right) do x_{3}.

$$x_{3}=-\frac{7}{5}$$

Cuir -\frac{7}{5} in ionad x_{3} sa chothromóid x_{2}=-\frac{1}{3}+\frac{1}{3}x_{3}.

$$x_{2}=-\frac{1}{3}+\frac{1}{3}\left(-\frac{7}{5}\right)$$

Ríomh x_{2} ó x_{2}=-\frac{1}{3}+\frac{1}{3}\left(-\frac{7}{5}\right).

$$x_{2}=-\frac{4}{5}$$

Cuir -\frac{4}{5} in ionad x_{2} agus -\frac{7}{5} in ionad x_{3} sa chothromóid x_{1}=x_{2}-x_{3}+2.

$$x_{1}=-\frac{4}{5}-\left(-\frac{7}{5}\right)+2$$

Ríomh x_{1} ó x_{1}=-\frac{4}{5}-\left(-\frac{7}{5}\right)+2.

$$x_{1}=\frac{13}{5}$$

Tá an córas réitithe anois.

$$x_{1}=\frac{13}{5} x_{2}=-\frac{4}{5} x_{3}=-\frac{7}{5}$$