document.write( "Question 1127777: At the football game, 3 hamburgers and 6 soft drinks cost $21, and 3 hamburgers and 3 soft drinks cost $15. Which two equations can be used to determine the price of a hamburger and the price of a soft drink?\r
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Algebra.Com's Answer #744243 by math_helper(2461)\"\" \"About 
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document.write( "(1)   3x + 6y = 21  \r\n" );
document.write( "(2)   3x + 3y = 15\r\n" );
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document.write( "                3y = 6
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document.write( "                 y = 2  —>  3x = 21-12 = 9 —> x = 3 
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document.write( "Cost of items:
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document.write( "Hamburg:  $3
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document.write( "Soft drink:  $2
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document.write( "Check:\r
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document.write( "3*3 + 6*2 = 9+12 = 21 ✔
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document.write( "3*3 + 3*2 = 9+6 = 15 ✔ \r
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