Final answer:
The equation of a line can be written in standard form as ax + by = c, where a, b, and c are constants.
Step-by-step explanation:
The equation of a line can be written in standard form as ax + by = c, where a, b, and c are constants. The values of a, b, and c can be determined from the given equation. In option a) ax + by = c, a = a, b = b, and c = 0. In option b) y = mx + b, there is no c term, so c = 0. In option c) a = y - bx, there is no c term, so c = 0. In option d) c = ax + by, a = 0, b = 0, and c = 0.