document.write( "Question 297903: Sofia is 5 times as old as her cousin. Four years from now she will be 3 times as old as her cousin. Whats the ages of both Sofia and her cousin? \n" ); document.write( "
Algebra.Com's Answer #214487 by Deina(147)\"\" \"About 
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Variables Used

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  • S = Sarah

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  • c = cousin

\n" ); document.write( "What do we know? We know that:
\n" ); document.write( "S = 5c
\n" ); document.write( "S + 4 = 3(c + 4)

\n" ); document.write( "Substitute \"5c\" for S in the second equation:
\n" ); document.write( "5c + 4 = 3(c + 4)

\n" ); document.write( "Distribute:
\n" ); document.write( "5c + 4 = 3c + 12

\n" ); document.write( "Subtract 3c from each side:
\n" ); document.write( "5c -3c + 4 = 12

\n" ); document.write( "Subtract 4 from each side:
\n" ); document.write( "2c = 8

\n" ); document.write( "Divide both sides by 2 and find that
\n" ); document.write( "c = 4

\n" ); document.write( "Substitute \"4\" for \"c\" in the 1st equation:
\n" ); document.write( "S = 5(4) and we find that
\n" ); document.write( "Sarah is 20 years old and her cousin is 4 years old
\n" ); document.write( " & bob's your uncle!\r
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