The Characteristic Equation Of $A = \left( \begin{array} { l l } 2 & 2 \\1 & 1\end{array} \right)$

Multiple Choice

The characteristic equation of $A = \left( \begin{array} { l l } 2 & 2 \\1 & 1\end{array} \right)$ is

A) $\lambda ^ { 2 } + 3 \lambda - 4 = 0$
B) $\lambda ^ { 2 } + 3 \lambda + 4 = 0$
C) $\lambda ^ { 2 } - 3 \lambda = 0$
D) $\lambda ^ { 2 } + 3 \lambda = 0$
E) $\lambda ^ { 2 } - 3 \lambda - 4 = 0$