document.write( "Question 908864: Luis is 30 years younger than william. 15 years ago, william was 4 times as old as luis . How old is william? \n" ); document.write( "
Algebra.Com's Answer #551378 by KlambinRonsentaswer(36)\"\" \"About 
You can put this solution on YOUR website!
Hey.I'm glad to help you.But my English isn't very well and I hope you don't mind it.\r
\n" ); document.write( "\n" ); document.write( "The answer is 55.\r
\n" ); document.write( "\n" ); document.write( "let William's age = x
\n" ); document.write( "let Luis's age =x-30\r
\n" ); document.write( "\n" ); document.write( " x-15 = 4·(x-30-15)
\n" ); document.write( " x-15 = 4·(x-45)
\n" ); document.write( " x-15 = 4x-45×4
\n" ); document.write( " x-15 = 4x-180
\n" ); document.write( " 4x-x = 180-15
\n" ); document.write( " 3x = 165
\n" ); document.write( " x = 165÷3
\n" ); document.write( " x = 55
\n" ); document.write( "So William is 55 years old now.\r
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