document.write( "Question 1009040: If y is directly proportional to the square root of x and y = −32 when x = 400, find y if x = 160000. (Round off your answer to the nearest hundredth.) \n" ); document.write( "
Algebra.Com's Answer #624636 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( " If \"y+\"is directly proportional to the \"sqrt%28x+%29\", we have
\n" ); document.write( "\"y+=k%2Asqrt%28x+%29\"\r
\n" ); document.write( "\n" ); document.write( "and if \"y+=+-32\" when \"x+=+400\", we can find a constant \"k\"\r
\n" ); document.write( "\n" ); document.write( "\"-32+=k%2Asqrt%28400+%29\"\r
\n" ); document.write( "\n" ); document.write( "\"-32+=k%2A20+\"\r
\n" ); document.write( "\n" ); document.write( "\"k=+-32%2F20\"\r
\n" ); document.write( "\n" ); document.write( "\"k=+-8%2F5\"\r
\n" ); document.write( "\n" ); document.write( "so, equation is: \"y+=+%28-8%2F5%29%2Asqrt%28x+%29\"\r
\n" ); document.write( "\n" ); document.write( " if \"x+=+160000\", then\r
\n" ); document.write( "\n" ); document.write( "\"y+=+%28-8%2F5%29%2Asqrt%28160000+%29\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=+%28-8%2Fcross%285%29%29%2Across%28400%2980+\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=+-8%2A80+\"\r
\n" ); document.write( "\n" ); document.write( "\"y+=+-640+\"\r
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