Solving Systems with Inverses · Exercise 9

Show that matrix $A$ is the inverse of matrix $B.$

$A=\left[\begin{array}{cc}1& 0\\ -1& 1\end{array}\right],B=\left[\begin{array}{cc}1& 0\\ 1& 1\end{array}\right]$

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Algebra and Trigonometry 2e · §11.7 Solving Systems with Inverses · Exercise 9