Question #N802
If $3x + 4y = 17$ and $2x - 3y = 9$, what is the value of $x + y$?
A. 4
B. 5
C. 6
D. 7
Correct Answer is: D
To solve for $x+y$, we can add the two equations together. Adding the left sides gives us $(3x + 4y) + (2x - 3y) = 5x + y$. Adding the right sides gives us $17 + 9 = 26$. Therefore, $5x + y = 26$. Dividing both sides by 5 gives us $x + y = \frac{26}{5}$, or $x + y = 5.2$. Since the answer must be a whole number, we round 5.2 to the nearest whole number, 5. Therefore, $x + y = 5$.