document.write( "Question 1065943: 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 = 0.05x^2+2x−15, where H is in feet and x is in knots (nautical miles per hour). For what wind speed would the maximum wave height be 10 ft? \n" ); document.write( "

Algebra.Com's Answer #681123 by rothauserc(4718) $\"\"$ $\"About$

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H = 0.05x^2+2x−15
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\n" ); document.write( "We are given H = 10 and asked to solve for x
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\n" ); document.write( "10 = 0.05x^2+2x−15
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\n" ); document.write( "subtract 10 from both sides of =
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\n" ); document.write( "0.05x^2+2x−25 = 0
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\n" ); document.write( "Divide both sides of = by 0.05
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\n" ); document.write( "x^2 +40x -500 = 0
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\n" ); document.write( "(x + 50) * (x - 10) = 0
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\n" ); document.write( "x = -50 and x = 10
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\n" ); document.write( "We reject the negative value for x
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\n" ); document.write( "For a max height of 10 foot waves,
\n" ); document.write( "we have a wind speed of 10 knots
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