document.write( "Question 1071931: A motel in New Orleans charges $90 per day for double occupancy and $80 per day for single occupancy. If 80 rooms are occupied for a total of $6930, how many rooms of each kind are there? \n" ); document.write( "

Algebra.Com's Answer #686833 by ikleyn(52824) $\"\"$ $\"About$

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document.write( "You math model is this system of two linear equations in two unknowns\r\n" );
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document.write( "  x +   y =   80,     (1)\r\n" );
document.write( "90x + 80y = 6930.     (2)\r\n" );
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document.write( "Can you solve it ?\r\n" );
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document.write( "Do you know how to solve it ?\r\n" );
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document.write( "HINT: express x = 80 - y from (1) and then substitute it into (2) replacing x.\r\n" );
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document.write( "You will obtain a single equation for y, which you can easily solve.\r\n" );
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document.write( "This is \"the Substitution method\".\r\n" );
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