document.write( "Question 453346: How do you know if the inverse of a graph is not a function by looking at a graph? \n" ); document.write( "
Algebra.Com's Answer #311492 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "By observing that it passes both the vertical line test\r\n" );
document.write( "(necessary for being a function) and also the horizontal\r\n" );
document.write( "line test (for having an inverse which is a function.\r\n" );
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document.write( "This is explained well at this Iowa site:\r\n" );
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document.write( "http://www.uiowa.edu/~examserv/mathmatters/tutorial_quiz/geometry/vertandhorizlinetests.html\r\n" );
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document.write( "Edwin
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