Answer:
15) 55°
16) 90°
Step-by-step explanation:
15)
55° + 75° + x = 180°
x = 50°
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50° + 60° + x = 180°
x = 70°
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70° + 55° + ? = 180°
? = 55°
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16)
55° + 90° + x = 180°
x = 35°
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35° + x = 90°
x = 55°
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55° + 35° + ? = 180°
? = 90°
