document.write( "Question 985014: Alex's dad is 45 which is twice the age plus 15 years of Billy. How old is BIlly? \n" ); document.write( "
Algebra.Com's Answer #605856 by macston(5194)\"\" \"About 
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\n" ); document.write( "B=Billy's age; D=Dad's age
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\n" ); document.write( "D=2B+15yrs
\n" ); document.write( "45yrs=2B+15yrs
\n" ); document.write( "30yrs=2B
\n" ); document.write( "15yrs=B
\n" ); document.write( "ANSWER: Billy is 15 years old.
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