document.write( "Question 236513: If 5 times the first number plus three times the second number equals 47, and 10 times the first number minus 4 times the second number equals 54, what are the numbers? \n" ); document.write( "
Algebra.Com's Answer #174091 by Anthea Lawn(22)\"\" \"About 
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okay, call the first number x and the second number y\r
\n" ); document.write( "\n" ); document.write( "5x + 3y = 47
\n" ); document.write( "10x -4y = 54\r
\n" ); document.write( "\n" ); document.write( "So now we have two simultaneous equations. Double everything in the top equation :\r
\n" ); document.write( "\n" ); document.write( "10x + 6y = 94\r
\n" ); document.write( "\n" ); document.write( "Now both equations start with a 10x So take the second equation away from the new top one and the 10x bits will disappear :\r
\n" ); document.write( "\n" ); document.write( "(10x - 10x) + 6y - (-4y) = 94 - 54\r
\n" ); document.write( "\n" ); document.write( "10y = 40 (because taking away a minus equals a plus)\r
\n" ); document.write( "\n" ); document.write( "y = 4\r
\n" ); document.write( "\n" ); document.write( "Substituting back into either of the original equations gives x = 7\r
\n" ); document.write( "\n" ); document.write( "So the two numbers are 7 and 4.
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