Answer:
∠RYF = 68º
Step-by-step explanation:
The angles are supplementary
(4c + 72) + (5c + 18) = 180
Combine like terms
9c + 90 = 180
Subtract 90 from both sides
9c = 90
Divide both sides by 9
c = 10
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∠RYF = 5c + 18
∠RYF = 5(10) + 18
∠RYF = 50 + 18
∠RYF = 68
