Solve the system: 2x + y = 7 and x - y = 1.

• A. x = 6/3, y = 5/3
• B. x = 4, y = 3
• C. x = 8/3, y = 7/3
• D. x = 8/3, y = 5/3

Answer: (D)

Solving two linear equations by elimination. Add the two equations to cancel y: (2x + y) + (x − y) = 7 + 1, which gives 3x = 8, so x = 8/3. Then use x − y = 1 to find y: 8/3 − y = 1, which leads to y = 8/3 − 1 = 5/3. So the solution is x = 8/3 and y = 5/3. This pair satisfies both original equations (2x + y = 7 and x − y = 1), confirming it is correct.