document.write( "Question 1091203: A woman is 4 time older than her child.5 years ago the product of their ages was 175.find their present ages \n" ); document.write( "
Algebra.Com's Answer #705580 by ankor@dixie-net.com(22740)\"\" \"About 
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w = the woman's present age
\n" ); document.write( "c = the child's
\n" ); document.write( ":
\n" ); document.write( "Write an equation for each statement
\n" ); document.write( ":
\n" ); document.write( "A woman is 4 time older than her child.
\n" ); document.write( "w = 4c
\n" ); document.write( "5 years ago the product of their ages was 175.
\n" ); document.write( "(w-5)*(c-5) = 175
\n" ); document.write( "replace w with 4c
\n" ); document.write( "(4c-5)*(c-5) = 175
\n" ); document.write( "FOIL
\n" ); document.write( "4c^2 - 20c - 5c + 25 = 175
\n" ); document.write( "4c^2 - 25c + 25 - 175 = 0
\n" ); document.write( "a quadratic equation
\n" ); document.write( "4c^2 - 25c - 150 = 0
\n" ); document.write( "We can use the quadratic formula; a=4; b=-25; c=-150, but this will factor to
\n" ); document.write( "(4c+15)(c-10) = 0
\n" ); document.write( "the positive solution is all we want here
\n" ); document.write( "c = 10 yrs old the child's age
\n" ); document.write( "then obviously
\n" ); document.write( "4(10) = 40 yrs is the woman's age
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check this solution in the statement
\n" ); document.write( "\"5 years ago the product of their ages was 175\"
\n" ); document.write( "(40-5) * (10-5) =
\n" ); document.write( "35 * 5 = 175 \n" ); document.write( "
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