Question

which angles are supplementary to each other? ∠1 and ∠9 ∠15 and ∠13 ∠15 and ∠16 ∠13 and ∠10

Explanation:

Step1: Recall supplementary - angle definition

Two angles are supplementary if their sum is 180 degrees. Adjacent angles that form a straight - line are supplementary.

Step2: Analyze each pair

• For ∠1 and ∠9, they are not adjacent and do not form a straight - line, so they are not supplementary.
• For ∠15 and ∠13, they are adjacent and form a straight - line. So, ∠15+∠13 = 180 degrees, and they are supplementary.
• For ∠15 and ∠16, they are adjacent and form a straight - line. So, ∠15+∠16 = 180 degrees, and they are supplementary.
• For ∠13 and ∠10, they are not adjacent and do not form a straight - line, so they are not supplementary.

Answer:

∠15 and ∠13; ∠15 and ∠16