Question

Calculating the Slope of a Line

You have discovered another alien. Find the correct rescue path before answering this question.

Which statements are true about the equation of the line used to save this alien?
The y-intercept is not visible on the graph.
The slope does not exist for this line.
The y-intercept is positive.
The line crosses the x-axis at –3.

Answer 1

True: 1, 2, and 4. False: 3.

Reasoning:
- The line is vertical at x = −3, so it crosses the x-axis at (−3, 0) — statement 4 is true.
- A vertical line has undefined slope, so statement 2 is true.
- A vertical line does not meet the y-axis (no y-intercept), so the y-intercept is not visible/does not exist — statement 1 is true.
- Therefore the y-intercept cannot be a positive number — statement 3 is false.