2x + y = 5
Put the coordinates of the points to the equation and check it:
A. 5 - not make sense
B. (1, 2) - x = 1, y = 2
2(1) + 2 = 2 + 2 = 4 ≠ 5 NOT
C. (2, -1) - x = 2, y = -1
2(2) + (-1) = 4 - 1 = 2 ≠ 5 NOT
D. (3, -1) - x = 3, y = -1
2(3) + (-1) = 6 - 1 = 5 YES
Answer: D. (3, -1).
