SOLUTION: This is a problem from a textbook that I just do not understand how to solve. I have been reading it over and over and still don't get it. Can you please help? Sailboat speed. Th

Algebra ->  Radicals -> SOLUTION: This is a problem from a textbook that I just do not understand how to solve. I have been reading it over and over and still don't get it. Can you please help? Sailboat speed. Th      Log On


   

Question 39600: This is a problem from a textbook that I just do not understand how to solve. I have been reading it over and over and still don't get it. Can you please help?
Sailboat speed. The sail area-displacement ratio S provides a measure of the sail power available to drive a boat. For a boat with a displacement of d pounds and a sail area of A square feet S = 16Ad^-2/3
a) Find s to the nearest tenth for the Tartan 4100, which has a sail area of 810 square feet and a displacement of 23,245 pounds.
b) Solve the formula for d.
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
a) Find S to the nearest tenth:
S+=+16Ad%5E%28-2%2F3%29 Substitute the given values of: A=810, d = 23,245.
S+=+16%28810%29%2F%2823245%29%5E%282%2F3%29
S+=+12960%2F814.5
S+=+15.9 To the nearest tenth.
b) Solve the formula for d.
S+=+16Ad%5E%28-2%2F3%29 Multiply both sides by d%5E%282%2F3%29
Sd%5E%282%2F3%29+=+16A Divide both sides by S.
d%5E%282%2F3%29+=+16A%2FS Raise both sides to the 3/2 power.
d+=+%2816A%2FS%29%5E%283%2F2%29