document.write( "Question 137050: Find an equation of a hyperbola with vertices at (-9,4) and (-5,4) and asymptotes y=3x+25 and y=-3x-17. \r
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Algebra.Com's Answer #100296 by Edwin McCravy(20060)\"\" \"About 
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Find an equation of a hyperbola with vertices at (-9,4) and (-5,4) and asymptotes y=3x+25 and y=-3x-17. \r
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\n" ); document.write( "\n" ); document.write( "First let's draw the asymptotes and the vertices:\r
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\n" ); document.write( "\n" ); document.write( "We can tell that the hyperbola opens right and left
\n" ); document.write( "and has the equation\r
\n" ); document.write( "\n" ); document.write( "\"%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "where the center is \"%22%28h%2Ck%29%22\"
\n" ); document.write( "The length of the semi-transverse axis is \"a\"
\n" ); document.write( "The length of the semi-conjugate axis is \"b\"
\n" ); document.write( "The two asymptotes have slopes ±\"b%2Fa\" and pass
\n" ); document.write( "through the center (h,k).\r
\n" ); document.write( "\n" ); document.write( "The center is the midpoint between the vertices,
\n" ); document.write( "(-9,4) and (-5,4) which is the point (-7,4) \r
\n" ); document.write( "\n" ); document.write( "So (h,k) = (-7,4)\r
\n" ); document.write( "\n" ); document.write( "The transverse axis is the distance between the vertices
\n" ); document.write( "\"%22%28-9%2C4%29%22\" and \"%22%28-5%2C4%29%22\" which is \"4\" units.\r
\n" ); document.write( "\n" ); document.write( "So the semi-transverse axis is half of that or \"2\".
\n" ); document.write( "That is \"a=2\"\r
\n" ); document.write( "\n" ); document.write( "Since the asymptotes are \"y=3x%2B25\" and \"y=-3x-17\"
\n" ); document.write( "We compare them to \"y=mx%2BB\" and find that their slopes
\n" ); document.write( "are ±\"3\",\r
\n" ); document.write( "\n" ); document.write( "Since the slope are ±\"b%2Fa\", then\r
\n" ); document.write( "\n" ); document.write( "\"b%2Fa=3\" and since \"a=2\", we substitute that:\r
\n" ); document.write( "\n" ); document.write( "\"b%2F2=3\" or \"b=6\"\r
\n" ); document.write( "\n" ); document.write( "So the equation\r
\n" ); document.write( "\n" ); document.write( "\"%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "becomes\r
\n" ); document.write( "\n" ); document.write( "\"%28x-%28-7%29%29%5E2%2F2%5E2%2B%28y-4%29%5E2%2F6%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B7%29%5E2%2F4%2B%28y-4%29%5E2%2F36=1\"\r
\n" ); document.write( "\n" ); document.write( "Now we draw the defining rectangle which has base
\n" ); document.write( "2a and height 2b and has the center as its center.\r
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\n" ); document.write( "\n" ); document.write( "Now we can sketch in the hyperbola:\r
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