document.write( "Question 944760: mary is half as old as joseph. the sum of their ages is 51. how old are they now? \n" ); document.write( "
Algebra.Com's Answer #576042 by macston(5194)\"\" \"About 
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M is Mary's age. J is Joseph's age
\n" ); document.write( "J=2M; J+M=51 Substitute first equation for J in second equation
\n" ); document.write( "2M+M=51
\n" ); document.write( "3M=51 Divide by 3
\n" ); document.write( "M=17 ANSWER 1: Mary is 17
\n" ); document.write( "J=2M
\n" ); document.write( "J=2(17)
\n" ); document.write( "J=34 ANSWER 2: Joseph is 34
\n" ); document.write( "CHECK
\n" ); document.write( "M+J=51
\n" ); document.write( "17+34=51
\n" ); document.write( "51=51
\n" ); document.write( "
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