Solve for $X$:
$$ \left[ \begin{array}{cc} 2 & 5 \\ 0 & 0 \\ \end{array} \right ] - X \left [ \begin{array}{cc} -7 & 8 \\ 7 & -7 \\ \end{array} \right ] \;\;=\;\; I $$ $X$ is an unknown $2\times 2$ matrix.
I'm not exactly sure how to solve for this matrix. I know that $I$ stands for a matrix multiplied by the inverse matrix, but I do not know which one. Could someone help me out on this?
$I$ stands for the identity matrix, i.e. $$I = \begin{pmatrix} 1 & 0 \\ 0 & 1\end{pmatrix}$$ Write $$ X = \begin{pmatrix} a & b \\ c & d\end{pmatrix}$$ and then you just have to find $a,b,c,d$ by remembering how to multiply matrixes.