How do you find the inverse of A=((-4, 8), (2, -4))?

Feb 18, 2016

I believe $\left(\begin{matrix}- 4 & 8 \\ 2 & - 4\end{matrix}\right)$ does not have an inverse.

Explanation:

The rows of $A$ are not independent.

Row 2 is simply Row 1 multiplied by $\left(- \frac{1}{2}\right)$

Think of this as like being asked to solve
$\left\{\begin{matrix}k \left(a x\right) + k \left(b y\right) = {c}_{1} \\ m \left(a x\right) + m \left(b y\right) = {c}_{2}\end{matrix}\right.$
which has no proper solution.