document.write( "Question 1002617: Which equation is the equation of a line that passes through (–10, 3) and is perpendicular to y = 5x – 7? (1 point)
\n" ); document.write( " y = 5x + 53
\n" ); document.write( " y = –1/5x – 7
\n" ); document.write( " y = –1/5x + 1
\n" ); document.write( " y = 1/5x + 5
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Algebra.Com's Answer #619483 by Edwin McCravy(20056)\"\" \"About 
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document.write( "y = 5x – 7 has slope which is the coefficient of x or 5.\r\n" );
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document.write( "A line perpendicular to that line would have a slope which\r\n" );
document.write( "is its negative reciprocal or -1/5, so that narrows the \r\n" );
document.write( "correct choice down to either y = –1/5x – 7 or y = –1/5x + 1.\r\n" );
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document.write( "So we need only to find out which one is satisfied by (-10,3).\r\n" );
document.write( "Substituting x=-10 and y = 3 in\r\n" );
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document.write( "y = –1/5x – 7\r\n" );
document.write( "3 = -1/5(-10) - 7\r\n" );
document.write( "3 = 2-7\r\n" );
document.write( "3 = -5\r\n" );
document.write( "That's false, so that's not it.\r\n" );
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document.write( "So it can only be \r\n" );
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document.write( "y = –1/5x + 1.   Check to make sure:\r\n" );
document.write( "3 = -1/5(-10) + 1\r\n" );
document.write( "3 = 2+1\r\n" );
document.write( "3 = 3\r\n" );
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document.write( "That's true.  So the answer is y = –1/5x + 1\r\n" );
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document.write( "Edwin
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