Question

which angles are supplementary to each other? ∠13 and ∠9 ∠9 and ∠4 ∠7 and ∠9 ∠10 and ∠11

Explanation:

Step1: Recall supplementary - angle definition

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

Step2: Analyze each pair

• For ∠13 and ∠9: They are adjacent and form a straight - line. So, ∠13+∠9 = 180°.
• For ∠9 and ∠4: They are not adjacent and do not form a straight - line, so they are not supplementary.
• For ∠7 and ∠9: They are not adjacent and do not form a straight - line, so they are not supplementary.
• For ∠10 and ∠11: They are adjacent but do not form a straight - line, so they are not supplementary.

Answer:

∠13 and ∠9