Answer: 
Step-by-step explanation:
Geometric mean= Number of terms root of the product of all the terms of that sequence
sqrt(2sqrt(5)*5sqrt(2))= 10sqrt(10)
So the “certain number” will be S.
Since 2width + 2length, the first part would be 2 times 2 which is 4
The length is S - 3
We then have to multiply this by 2
So it is 2(S-3) which is 2S-6
So the answer is 4+2S-6 which is 2S-2
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Answer:
139.7124
Step-by-step explanation:
9.6+5.42-3.2 (^2)
11.82^2
= 139.7124