- [[linear combination of columns]], [[linear combinations]] # Idea If we pre-multiply matrix $A$ by vector $x$, we're taking the linear combination of matrix $A$. This operation is a **row operation** and is used in [[elimination matrix|elimination matrices]]. A row times a matrix gives us a row. ![[s20220725_012916.png]] $xA$ ![[s20220725_012256.png]] # References - [2. Elimination with Matrices. - YouTube](https://youtu.be/QVKj3LADCnA?t=1290)