document.write( "Question 1200158: State whether the relationship between the variables in the table is a direct variation, an inverse variation, or neither. If it is a direct or inverse variation, write a function to model it.
\n" ); document.write( "x 3 9 13 20
\n" ); document.write( "y 9 27 39 60
\n" ); document.write( "i know its direct veration and y=3x
\n" ); document.write( "but how? \n" ); document.write( "

Algebra.Com's Answer #834197 by ikleyn(52786) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "To check the formula, simply substitute value of x from the table into the right side of the formula \r\n" );
document.write( "and calculate its value; then compare with the corresponding value of y from the table.\r\n" );
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document.write( "You will see that every time the formula produces a correct value.\r\n" );
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document.write( "It justifies the solution (the formula).\r\n" );
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document.write( "If you want to know how to deduce this formula on your own, \r\n" );
document.write( "divide a value of y from the table by the corresponding value of x.\r\n" );
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document.write( "Every time you will get the same value of 3:\r\n" );
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document.write( "     = 3.\r\n" );
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document.write( "It means that  y = 3x  for all given points and that the relationship is this linear function.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, with detailed explanations.\r
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