Question

a system with one solution occurs when the lines dropdown.

Explanation:

Understand the geometric meaning of a system of equations

Using the System of Equations Definition knowledge point

$$ \text{A system of linear equations represents two or more lines on a coordinate plane.} $$

Determine the condition for exactly one solution

Using the Graphical Solution of Systems knowledge point

$$ \text{A solution to a system is a point where the lines intersect. Exactly one solution means they intersect at exactly one point, which occurs when the lines intersect.} $$

Answer:

A system with one solution occurs when the lines <blank>intersect</blank>.