Make the equation of the straight line passing through the given two points A (2; 0) B (0; 1).

We will use the fact that the equation of a straight line passing through two given points M1 (x1, y1) and M2 (x2, y2) can be represented as (x – x1) / (x2 – x1) = (y – y1) / (y2 – y1) or (x – x2) / (x1 – x2) = (y – y2) / (y1 – y2).
In the task, points A and B are specified by coordinates: A (2; 0) and B (0; 1). Therefore, the equation of the line AB has the form: (x – 2) / (0 – 2) = (y – 0) / (1 – 0) or (x – 2) / (–2) = y / 1. Multiply both sides the obtained equation by (–2). Then we have: x – 2 = (–2) * y or x + 2 * y – 2 = 0.
Answer: The equation of a straight line passing through the given two points A (2; 0) and B (0; 1) has the form x + 2 * y – 2 = 0.