Incorrect

Correct!

The correct answer is G.

If x + 2y = 1, then x = 1 – 2y. Substituting into 2x + y = 5, 2(1 – 2y) + y = 5, 2 – 4y + y = 5, 2 – 3y = 5, –3y = 3, y = –1. Then x = 1 – 2(–1) = 1 + 2 = 3.

Check: If x = 3 and y = –1, 3 + 2(–1) = 3 – 2 = 1 and 2(3) + (–1) = 6 – 1 = 5,
so the solution for the system is x = 3 and y = –1 and then x + y = 2.

F, H, J, K. x + 2y = 1 and 2x + y = 5 are different nonparallel lines because the slope of the first line is – and the slope of the second line is –2. Different nonparallel lines intersect in at most one point and that point is (3,–1). The sum of any two numbers is unique, so none of the other answers can be correct.

Incorrect

Incorrect

Incorrect