document.write( "Question 772235: the square of my youngest child's age is 9 more then the product of 17 and the age of my oldest child. my oldest child is 3 years older than my youngest child. How old are my children?\r
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Algebra.Com's Answer #470793 by KMST(5328)\"\" \"About 
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\"x\"= age of youngest child
\n" ); document.write( "\"y\"= age of oldest child
\n" ); document.write( "So
\n" ); document.write( "\"x%5E2\"= the square of the youngest child's age
\n" ); document.write( "\"17y\"= the product of 17 and the age of the oldest child
\n" ); document.write( "\"17y%2B9\"= 9 more then the product of 17 and the age of the oldest child
\n" ); document.write( "\"The square of my youngest child's age is 9 more then the product of 17 and the age of my oldest child\" translates as
\n" ); document.write( "\"x%5E2=17y%2B9\"
\n" ); document.write( "\"My oldest child is 3 years older than my youngest child\" translates as
\n" ); document.write( "\"y=x%2B3\"
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\n" ); document.write( "We need to solve the system
\n" ); document.write( "\"system%28x%5E2=17y%2B9%2Cy=x%2B3%29\"
\n" ); document.write( "Substituting \"y=x%2B3\" into the other equation we get
\n" ); document.write( "\"x%5E2=17%28x%2B3%29%2B9\" --> \"x%5E2=17x%2B51%2B9\" --> \"x%5E2=17x%2B60\" --> \"x%5E2-17x-60=0\"
\n" ); document.write( "That quadratic equation can be solved several ways.
\n" ); document.write( "For me, the easiest way is by factoring:
\n" ); document.write( "\"x%5E2-17x-60=0\" --> \"%28x-20%29%28x%2B3%29=0\"
\n" ); document.write( "The solutions are:
\n" ); document.write( "\"x-20=0\" --> \"highlight%28x=20%29\" and
\n" ); document.write( "\"x%2B3=0\" --> \"x=-3\", which does not make sense, because no person can have a negative age.
\n" ); document.write( "From \"highlight%28x=20%29\" (and \"y=x%2B3\"), we get
\n" ); document.write( "\"y=20%2B3\"--> \"highlight%28y=23%29\"\r
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