document.write( "Question 76007This question is from textbook Algebra 1
\n" ); document.write( ": Zelma is 18 years older than her son. She was 3 times as old as he was 1 year ago. How old are they now? \n" ); document.write( "
Algebra.Com's Answer #54607 by ankor@dixie-net.com(22740)\"\" \"About 
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Let z = Zel's age now; Let s = son's age now
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\n" ); document.write( "\"Zelma is 18 years older than her son.\" says:
\n" ); document.write( "z = (s + 18)
\n" ); document.write( "or
\n" ); document.write( "s = (z - 18)
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\n" ); document.write( "\"She was 3 times as old as he was 1 year ago.\" says:
\n" ); document.write( "(z-1) = 3(s-1)
\n" ); document.write( "z - 1 = 3s - 3
\n" ); document.write( "z = 3s - 3 + 1
\n" ); document.write( "z = 3s - 2
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\n" ); document.write( "How old are they now?
\n" ); document.write( ":
\n" ); document.write( "Substitute (z-18) for s, in z = 3s - 2
\n" ); document.write( "z = 3(z-18) - 2
\n" ); document.write( "z = 3z - 54 - 2
\n" ); document.write( "z - 3z = -56
\n" ); document.write( "-2z = -56
\n" ); document.write( "z = -56/-2
\n" ); document.write( "z = +28 yrs old; then s = 28 -18 = 10 yrs old
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\n" ); document.write( "Check:
\n" ); document.write( "(28-1) = 3(10-1)
\n" ); document.write( " 27 = 3(9) \n" ); document.write( "
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