document.write( "Question 1061800: Every boy had 5 hot dogs and 7 sodas. Every girl had 3 hot dogs and 4 sodas. Together, the children ate 51 hot dogs and 70 sodas. How many children were there?
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Algebra.Com's Answer #676542 by Theo(13342)\"\" \"About 
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let x = number of boys
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\n" ); document.write( "\n" ); document.write( "since each boy ate 5 hot dogs and each girls ate 3 hot dogs and the total number of hot dogs eaten were 51, you get:\r
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\n" ); document.write( "\n" ); document.write( "5x + 3y = 51\r
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\n" ); document.write( "\n" ); document.write( "since each boy drank 7 sodas and each girl drank 4 sodas and the total number of sodas that were drunk was 70, you get:\r
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\n" ); document.write( "\n" ); document.write( "7x + 4y = 70\r
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\n" ); document.write( "\n" ); document.write( "these are two equations that need to be solved simultaneously.\r
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\n" ); document.write( "\n" ); document.write( "once solved, you will get x = 6 and y = 7.\r
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\n" ); document.write( "\n" ); document.write( "i solved using elimination.\r
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\n" ); document.write( "\n" ); document.write( "i started with:\r
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\n" ); document.write( "\n" ); document.write( "5x + 3y = 51
\n" ); document.write( "7x + 4y = 70\r
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\n" ); document.write( "\n" ); document.write( "i multiplied both sides of the first equation by 7 and multiplied both sides of the second equation by 5 to get:\r
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\n" ); document.write( "\n" ); document.write( "35x + 21y = 357
\n" ); document.write( "35x + 20y = 350\r
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\n" ); document.write( "\n" ); document.write( "i then subtracted the second equation from the first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "y = 7\r
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\n" ); document.write( "\n" ); document.write( "i then replaced y with 7 in the first original equation to get:\r
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\n" ); document.write( "\n" ); document.write( "5x + 21 = 51\r
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\n" ); document.write( "\n" ); document.write( "i then solved for x to get x = 6.\r
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\n" ); document.write( "\n" ); document.write( "you can confirm the solution is good by replacing x with 6 and y with 7 in both equations to see that both equations are true.\r
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\n" ); document.write( "\n" ); document.write( "i did, and they are, so i can assume the solution is good.\r
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