|
Question 1065945: The height of waves in a storm depends on the speed of the wind. Assuming the wind has no obstructions for a long distance, suppose the maximum wave height H for a wind speed x can be approximated by H = 0.02x^2+0.8x−17, where H is in feet and x is in knots (nautical miles per hour). For what wind speed would the maximum wave height be 7 ft?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The height of waves in a storm depends on the speed of the wind. Assuming the wind has no obstructions for a long distance, suppose the maximum wave height H for a wind speed x can be approximated by H = 0.02x^2+0.8x−17, where H is in feet and x is in knots (nautical miles per hour). For what wind speed would the maximum wave height be 7 ft?
--------------------
H(x) = 0.02x^2+0.8x−17
-----
Solve:: 0.02x^2 + 0.8x - 17 = 7
----
0.02x^2 + 0.8x - 24 = 0
----
2x^2 + 80x - 2400 = 0
----
x^2 + 40x - 1200 = 0
----
(x-20)(x+60) = 0
-----
Positive solution::
x = 20 knots/hr
------------
Cheers,
Stan H.
-------------
|
|
|
| |
