Hey there! :)
Answer:

-1/5n + 7 = 2
Start by subtracting 7 from both sides:
-1/5n + 7 - (7) = 2 - (7)
-1/5n = -5
Multiply both sides by the reciprocal of -1/5, or -5.
(-5) · (-1/5n) = (-5) · (-5)
n = 25
If you are asking how long the string is or the hypotenuse it would be about 75.89466
1,2,3,6,18,108,1944,209952,
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