SOLUTION: Two angles are a linear pair. Half the meaure of the first plus 9 is equal the measure of the second. What are the measures of both angles?

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Question 934347: Two angles are a linear pair. Half the meaure of the first plus 9 is equal the measure of the second. What are the measures of both angles?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

If two angles are a linear pair, they are supplementary because they always add to 180°.
alpha%2Bbeta=180°.....eq.1
Half the meaure of the first angle alpha%2F2%2B9 is equal the measure of the second angle beta, we have
alpha%2F2%2B9=beta...eq.2...substitute in eq.1

alpha%2Balpha%2F2%2B9=180.....eq.1
2alpha%2F2%2Balpha%2F2=180-9
3alpha%2F2=171
3alpha=171%2A2
3alpha=342
alpha=342%2F3
highlight%28alpha=114%29°
find beta

alpha%2F2%2B9=beta...eq.2
114%2F2%2B9=beta
57%2B9=beta
highlight%28beta=66%29°