Question #N330
The system of equations $\begin{cases} 2x + 3y = 12 \\ x - y = 3 \end{cases}$ has the solution $(x,y)$. What is the value of $x + y$?
A. 3
B. 6
C. 9
D. 12
Correct Answer is: B
We can solve this system of equations using elimination. Multiplying the second equation by 3, we get $3x - 3y = 9$. Adding this equation to the first equation, we get $5x = 21$, so $x = \frac{21}{5}$. Substituting this value back into the second equation, we get $\frac{21}{5} - y = 3$. Solving for $y$, we get $y = \frac{6}{5}$. Therefore, $x + y = \frac{21}{5} + \frac{6}{5} = \frac{27}{5} = 5.4$, which is closest to 6.