Which angles are supplementary to each other? • Angle 7 and Angle 3
• Angle 9 and Angle 12
• Angle 6 and Angle 12
• Angle 12 and Angle 10​

∠7 and ∠3

Step-by-step explanation:

Supplementary angles are two angles that add up to 180. Looking at all the answer choices, B, C, and D have either Big-Big angle or Small-Small angle. What we need is Big-Small angle, which is ∠7 and ∠3.

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