Réitigh {l}{a+2b+c=1}{2a-b=3}{a+2c=+5}

$$\left\{ \begin{array} { l } { a + 2 b + c = 1 } \\ { 2 a - b = 3 } \\ { a + 2 c = + 5 } \end{array} \right.$$

Réitigh do a,b,c.

$$a=1$$

$$b=-1$$

$$c=2$$

Céimeanna gearra ag baint úsáid as ionadú

Réitigh a+2b+c=1 do a.

$$a=-2b-c+1$$

Cuir -2b-c+1 in ionad a sa dara agus sa tríú cothromóid.

$$2\left(-2b-c+1\right)-b=3 -2b-c+1+2c=5$$

Réitigh na cothromóidí seo do b agus c faoi seach.

$$b=-\frac{2}{5}c-\frac{1}{5} c=4+2b$$

Cuir -\frac{2}{5}c-\frac{1}{5} in ionad b sa chothromóid c=4+2b.

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

Réitigh c=4+2\left(-\frac{2}{5}c-\frac{1}{5}\right) do c.

$$c=2$$

Cuir 2 in ionad c sa chothromóid b=-\frac{2}{5}c-\frac{1}{5}.

$$b=-\frac{2}{5}\times 2-\frac{1}{5}$$

Ríomh b ó b=-\frac{2}{5}\times 2-\frac{1}{5}.

$$b=-1$$

Cuir -1 in ionad b agus 2 in ionad c sa chothromóid a=-2b-c+1.

$$a=-2\left(-1\right)-2+1$$

Ríomh a ó a=-2\left(-1\right)-2+1.

$$a=1$$

Tá an córas réitithe anois.

$$a=1 b=-1 c=2$$