document.write( "Question 627043: sally is four years older than helen. the product of there ages is 45, how old is sally?
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Algebra.Com's Answer #394604 by Maths68(1474)\"\" \"About 
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Let
\n" ); document.write( "Present age of Sally = s years old
\n" ); document.write( "Present age of Helen = h years old\r
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\n" ); document.write( "\n" ); document.write( "Sally is four years older than Helen
\n" ); document.write( "s=h+4...........(1)
\n" ); document.write( "The Product of their ages is 45
\n" ); document.write( "s*h=45...........(2)
\n" ); document.write( "Substitute the value of s from (1) to (2)
\n" ); document.write( "(h+4)*h=45
\n" ); document.write( "h^2+4h=45
\n" ); document.write( "h^2+4h-45=0
\n" ); document.write( "Now Solve for h
\n" ); document.write( "h^2+9h-5h-45=0
\n" ); document.write( "h(h+9)-5(h+9)=0
\n" ); document.write( "(h-5)(h+9)=0
\n" ); document.write( "h-5=0 or h+9=0
\n" ); document.write( "h=5 or h=-9 (inadmissible)
\n" ); document.write( "so
\n" ); document.write( "h=5
\n" ); document.write( "Put the value of 5 in (1)
\n" ); document.write( "s=h+4...........(1)
\n" ); document.write( "s=5+4
\n" ); document.write( "s=9\r
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\n" ); document.write( "\n" ); document.write( "Present age of Sally = s = 9 years old
\n" ); document.write( "Present age of Helen = h = 5 years old\r
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