For f(x) = -x + 8, which statement is true? Group of answer choices

f(x + k) = f(x) + k

f(x + k) = f(x) + f(k)

f(x - k) = f(x) - k

f(x - k) = f(x) + k

What will the graph look like for a system of equations that has no solution? a. the lines will be perpendicular. b. the lines will cross at one point. c. both equations will form the same line. d. the lines will be parallel.