Final answer:
The correct rotation rule for a 90° counterclockwise rotation of a parallelogram is (x, y) → (-y, x). Using this rule, point A would be transformed to new coordinates A', which is given as (-1, -5) in option b, assuming the original coordinates of A allow for this result after applying the transformation rule.
Step-by-step explanation:
The student asked about the rule for rotating a parallelogram 90° counterclockwise and the new coordinates for point A after the rotation. The correct transformation rule that applies to a 90° counterclockwise rotation is (x, y) → (-y, x), which effectively swaps the x and y values and changes the sign of the original y-value. Considering the rule and if the original coordinates of point A are known, we can apply this transformation to find the new location of A', which is denoted as point A'.
However, since the original coordinates of A are not provided, it is critical to determine the correct rule. Based on the provided choices, the correct one is option b. (x, y) → (-y, x). For this rotation, the y coordinate becomes the negative x coordinate, and the x coordinate becomes the positive y coordinate. Using the given options, option b also suggests that A' is at (-1, -5), assuming the original point A had coordinates which, when transformed using the given rule, would result in those coordinates for A'.