4
algebraWhich graph shows a line with an undefined slope?
A
A vertical line
B
A horizontal line
C
A line rising to the right
D
A line falling to the right
Correct Answer: A
Choice A is the correct answer. Vertical lines have undefined slope.
- Definition: Slope is rise/run. Vertical lines have 0 run.
- Result: Division by zero is undefined.
💡 Strategic Tip: Vertical = Undefined. Horizontal = Zero.
Choice B is incorrect because slope is 0. Choice C is incorrect because slope is positive. Choice D is incorrect because slope is negative.