## Precalculus (6th Edition) Blitzer

$(2,-1)$
Step 1. Multiply 2 to the first equation and multiply 3 to the second equation: $\begin{cases}6x+8y=4\\6x+15y=-3 \end{cases}$ Step 2. Taking the difference between the two, we have $7y=-7$; thus $y=-1$ Step 3. Back-substitute $y=-1$ in either equation; we have $3x-4=2$ and thus $x=2$ Step 4. The solution is $(2,-1)$