System of Equations Shortcut

<p><a target="_blank" href="https://www.prepswift.com/quizzes/quiz/prepswift-system-of-equations-shortcut">System of Equations Shortcut Exercise</a></p><p>The GRE sometimes likes to be a little cheeky and provide a <span style="color:#27ae60;">Systems of Equations Shortcut</span> to solve a problem. If the problem is asking you for $x+y$ or $x-y$, rather than simply $x$ or $y$, that&#39;s an indication that the shortcut might apply.</p> <p style="margin-left: 40px;"><span style="color:#e74c3c;">Example</span></p> <p>$$3x+2y=10$$</p> <p>$$2x+3y=30$$</p> <p style="text-align: center;">What does $x+y$ equal? Adding the two equations together, we get...</p> <p>$$5x+5y=40$$</p> <p style="text-align: center;">Dividing both sides by $5$, we get...</p> <p>$$x+y=8$$</p> <p style="text-align: center;">Problem solved. Nice!</p>