Question

in the cube shown below, which lines are intersecting? select all that apply.

Explanation:

Step1: Recall intersecting lines definition

Intersecting lines share a common point.

Step2: Analyze each pair

• For $\overrightarrow{DE}$ and $\overrightarrow{EI}$: They meet at point $E$.
• For $\overrightarrow{BC}$ and $\overrightarrow{CG}$: They meet at point $C$.
• For $\overrightarrow{CG}$ and $\overrightarrow{FG}$: They meet at point $G$.
• For $\overrightarrow{CD}$ and $\overrightarrow{GH}$: In 3 - D space of cube, they do not intersect (they are skew lines).

Answer:

$\overrightarrow{DE}$ and $\overrightarrow{EI}$, $\overrightarrow{BC}$ and $\overrightarrow{CG}$, $\overrightarrow{CG}$ and $\overrightarrow{FG}$