document.write( "Question 647520: a sports arena was d years old 15 years ago \n" ); document.write( "
Algebra.Com's Answer #406262 by swincher4391(1107)\"\" \"About 
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Let s be the current age of the sports arena.
\n" ); document.write( "Let d be how old the sports arena was 15 years ago.\r
\n" ); document.write( "\n" ); document.write( "d = s-15
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