Question

Lee always uses the y-axis as her vertical line when testing whether a graph represents a function. Why is this strategy flawed? A The y-axis is a horizontal line. B The y-axis is infinitely long. C The y-axis is exempted from the vertical line test. D The y-axis only tests whether x = 0 has been mapped to more than one y coordinate

Answer 1

D) The y-axis only tests whether x = 0 has been mapped to more than one y coordinate.

Explanation:

The y-axis is a vertical line and intersects the x-axis (horizontal line) at the origin (0, 0) when both x and y are zero.

Vertical line test

A graph represents a function if and only if all vertical lines intersect the graph at most once.

Therefore, the strategy of using only the y-axis as the vertical line in the vertical line test is flawed because the y-axis only tests whether x = 0 has been mapped to more than one y-coordinate.