document.write( "Question 976192: A man is 4times as old as his son and five years ago the product of their ages is 234 find their present ages? \n" ); document.write( "
Algebra.Com's Answer #597873 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
let m = the man's age
\n" ); document.write( "let s = the son's age
\n" ); document.write( ":
\n" ); document.write( "A man is 4 times as old as his son
\n" ); document.write( "m = 4s
\n" ); document.write( ":
\n" ); document.write( "five years ago the product of their ages is 234
\n" ); document.write( "(m-5)(s-5) = 234
\n" ); document.write( "replace m with 4s
\n" ); document.write( "(4s-5)(s-5) = 234
\n" ); document.write( "FOIL
\n" ); document.write( "4s^2 - 20s - 5s + 25 = 234
\n" ); document.write( "Combine to form a quadratic equation
\n" ); document.write( "4s^2 - 25s + 25 - 234 = 0
\n" ); document.write( "4s^2 - 25s - 209 = 0
\n" ); document.write( "Use the quadratic formula; a=4; b=-25; c=-209
\n" ); document.write( "I got a positive solution of:
\n" ); document.write( "s = 11 yr is the son's age
\n" ); document.write( "then
\n" ); document.write( "4(11) = 44 yrs is the man's age
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "see if the product (5 yrs ago) checks out: (11-5) * (44-5) = 234\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );