document.write( "Question 102599: The sum of two numbers is 70. The second is 1 more than 2 times the first. What are the two numbers? \n" ); document.write( "
Algebra.Com's Answer #74606 by mjgulinello(10)\"\" \"About 
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Let M = the first number.
\n" ); document.write( "Let N = the second number.
\n" ); document.write( "We know the sum is 70, so
\n" ); document.write( "\"M+%2B+N+=+70\"
\n" ); document.write( "We also know the second number is 1 more than 2 times the first number, which we can express as
\n" ); document.write( "\"N+=+2M+%2B+1\"
\n" ); document.write( "Now use substitution and plug the second equation into the first.
\n" ); document.write( "\"M+%2B+%282M+%2B1%29+=+70\"
\n" ); document.write( "Combine like terms
\n" ); document.write( "\"3M+%2B+1++=+70\"
\n" ); document.write( "Subtract 1 from each side
\n" ); document.write( "\"3M+=+69\"
\n" ); document.write( "Divide each side by 3
\n" ); document.write( "\"M+=+23\"
\n" ); document.write( "Now we can plus this into the second equation.
\n" ); document.write( "\"N+=+2M+%2B+1\"
\n" ); document.write( "\"N+=+2+%2A+23+%2B+1\"
\n" ); document.write( "\"N+=+46+%2B+1\"
\n" ); document.write( "\"N=47\"
\n" ); document.write( "The two numbers are 23 and 47.
\n" ); document.write( "We can check this by plugging the numbers back into the first equation.
\n" ); document.write( "\"M+%2B+N+=+70\"
\n" ); document.write( "\"23+%2B+47+=+70\"
\n" ); document.write( "\"70=70\"
\n" ); document.write( "Check.
\n" ); document.write( "That's all for this problem.
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