## Precalculus (6th Edition) Blitzer

False. A true statement is: "a matrix row operation such as $\frac{-4}{5}{{R}_{1}}+{{R}_{2}}$ is permitted".
A matrix row operation can be performed by multiplying any row by a non-zero real number and adding one row to another row. Since ${{R}_{1}}$ is multiplied by $\frac{-4}{5}$ which is a real number and ${{R}_{2}}$ is added to $\frac{-4}{5}{{R}_{1}}$ the values obtained are real numbers. Therefore, the provided operation is permitted. So, the given statement is false. Hence, the provided statement is false and the true statement is: a matrix row operation such as $\frac{-4}{5}{{R}_{1}}+{{R}_{2}}$ is permitted.