## Precalculus (6th Edition) Blitzer

We have to use the elimination method to solve the provided linear system. Multiply equation (I) by 3 and subtract from equation (II) \begin{align} & \left( 3x+9y \right)-\left( 3x+9y \right)=6-6 \\ & 0=0 \end{align} So, according to equation (III) $0=0$ indicates that the system has infinitely many solutions. Thus, the system has infinitely many solutions.