document.write( "Question 626231: give exact and approximate solutions to three decimal place
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Algebra.Com's Answer #394045 by Edwin McCravy(20055)\"\" \"About 
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document.write( "y² - 14y + 49 = 25\r\n" );
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document.write( "You are able to recognize the right side, 25, as the square of an integer,\r\n" );
document.write( "since 25 = 5², from your knowledge of basic math.\r\n" );
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document.write( "You should now be able to recognize the left side, the trinomial \r\n" );
document.write( "y² - 14y + 49, as the square of a binomial, from your knowledge of algebra.\r\n" );
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document.write( "That's because it has four properties:\r\n" );
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document.write( "1.  The first term is a square, (y² is the square of y)\r\n" );
document.write( "2.  The third term +49 is also a square, (+49 is the square of 7)\r\n" );
document.write( "3.  The middle term, ignoring the sign, is twice the product of the square roots\r\n" );
document.write( "    of the first and third terms (-14y, ignoring the sign, 14y, is twice the\r\n" );
document.write( "    product of the square root of y², which is y, and the square root of 49,\r\n" );
document.write( "    which is 7, since 2·y·7 = 14y.)\r\n" );
document.write( "4.  It factors as the square of the sum of the square roots, using the\r\n" );
document.write( "    sign of the middle term as the sign of the second term of the binomial.\r\n" );
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document.write( "That's a lot to swallow, but it is to your advantage to be able to recognize\r\n" );
document.write( "that the left side factors as (y - 7)². So we have\r\n" );
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document.write( "y² - 14y + 49 = 25\r\n" );
document.write( "     (y - 7)² = 25\r\n" );
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document.write( "Now we use the principle of square roots:\r\n" );
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document.write( "      y - 7 = ±5\r\n" );
document.write( "          y = 7 ± 5\r\n" );
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document.write( "Using the + sign, y = 7 + 5 = 12\r\n" );
document.write( "Using the - sign, y = 7 - 5 = 2\r\n" );
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document.write( "Edwin
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