## Precalculus (6th Edition) Blitzer

We have to use the elimination method to solve provided system of equations. Multiply equation (II) by 2 and subtract from equation (I), \begin{align} & \left( 4x-2y \right)-\left( 4x-2y \right)=2-2 \\ & 0=0 \end{align} So, according to equation (III), $0=0$ indicates that the system has infinitely many solutions.