שינויים
/* פתרון */
c & d
\end{array}\right)\,|\,a-b-2c=0\}=
\{\left(\begin{array}{cc}
b+2c & b\\
c & d
\end{array}\right)\,|\,b,c,d\in \mathbb{R}\} =
span\{\left(\begin{array}{cc}
1 & 1\\
0 & 0
\end{array}\right),\left(\begin{array}{cc}
2 & 0\\
1 & 0
\end{array}\right),\left(\begin{array}{cc}
0 & 0\\
0 & 1
\end{array}\right)\}
</math>
