What is the relationship between the lines?
The lines are perpendicular
The lines are parallel but not identical
The lines intersect at one point
The lines are identical
Correct Answer: D
Choice D is the correct answer. Let's check if one equation is a multiple of the other.
Step 1: Multiply the first equation by 2:
This is exactly the second equation!
Step 2: Both equations represent the same line → identical (coincident) lines
This means infinitely many solutions.
💡 Strategic Tip: Identical lines are also called "coincident lines" and always give infinitely many solutions.
Choice A is incorrect because perpendicular lines have slopes whose product is -1. Here, both have slope .
Choice B is incorrect because the lines are not just parallel—they're the same line.
Choice C is incorrect because intersecting at one point requires different slopes.