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3 votes
What is the constant in

a) 9^n+10 + 3 = 81

b) 11^n−8 − 5 = 54

Edit: Never mind I figured it out this is a free 5-10 points answer whatever you want I won't delete it.
Good Luck.

User Seralo
by
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1 Answer

3 votes

Answer:

Part a)
n=-8.017176

Part b)
n=9.700465

Explanation:

Part a) we have


9^((n+10))+3=81

Solve for n

Subtract 3 both sides


9^((n+10))+3-3=81-3


9^((n+10))=78

take log both sides


log[9^((n+10))]=log[78]


(n+10)log[9]=log[78]


(n+10)=log[78]/log[9]


n=(log(78))/(log(9))-10 ----> using a calculator


n=-8.017176

Part b) we have


11^((n-8))-5=54

Solve for n

Adds 5 both sides


11^((n-8))-5+5=54+5


11^((n-8))=59

take log both sides


log[11^((n-8))]=log[59]


(n-8)log[11]=log[59]


(n-8)=log[59]/log[11]


n=(log(59))/(log(11))+8 ----> using a calculator


n=9.700465

User Dehli
by
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