Question

which angles are supplementary to each other?
image of angle diagram with angles labeled 1 - 12 and options: ∠4 and ∠2, ∠9 and ∠12, ∠3 and ∠8, ∠7 and ∠5

Explanation:

Step1: Define supplementary angles

Supplementary angles sum to $180^\circ$.

Step2: Analyze each option

• $\angle4$ and $\angle2$: Vertical angles, equal (not supplementary).
• $\angle9$ and $\angle12$: Vertical angles, equal (not supplementary).
• $\angle3$ and $\angle8$: They form a same-side interior angle pair between two intersecting lines, their sum is $180^\circ$.
• $\angle7$ and $\angle5$: Vertical angles, equal (not supplementary).

Answer:

$\angle3$ and $\angle8$