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If the geometric mean of a and 15 is 9√15, find the value of a.

1 Answer

2 votes
Answer: a = 81

Step-by-step explanation:

Geometric mean: sqrt a • b

sqrt a • 15 = 9 sqrt 15
Sqrt 15a = 9 sqrt 15
(Sqrt 15a)^2 = (9 sqrt 15)^2
15a = 81 x 15
a = 81
User Dallas Johnson
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