document.write( "Question 697627: A man is 37 years old and his child's age is 8. How many years ago was the product of their ages 96 \n" ); document.write( "

Algebra.Com's Answer #430179 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+x+\"$ = that number of years
\n" ); document.write( "given:
\n" ); document.write( " $\"+%28+37+-+x+%29%2A%28+8+-+x+%29+=+96+\"$
\n" ); document.write( " $\"+296+-+8x+-+37x+%2B+x%5E2+=+96+\"$
\n" ); document.write( " $\"+x%5E2+-+45x+%2B+200+=+0+\"$
\n" ); document.write( "Use quadratic formula
\n" ); document.write( " $\"x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"$
\n" ); document.write( " $\"+a+=+1+\"$
\n" ); document.write( " $\"+b+=+-45+\"$
\n" ); document.write( " $\"+c+=+200+\"$
\n" ); document.write( " $\"x+=+%28+-%28-45%29+%2B-+sqrt%28+%28-45%29%5E2+-+4%2A1%2A200+%29%29+%2F+%282%2A1%29+\"$
\n" ); document.write( " $\"x+=+%28+45+%2B-+sqrt%28+2025+-+800+%29%29+%2F+2+\"$
\n" ); document.write( " $\"x+=+%28+45+%2B-+sqrt%28+1225+%29%29+%2F+2+\"$
\n" ); document.write( " $\"x+=+%28+45+-+35%29+%2F+2+\"$
\n" ); document.write( " $\"+x+=+5+\"$
\n" ); document.write( "and also,
\n" ); document.write( " $\"+x+=+%28+45+%2B+35+%29+%2F+2+\"$
\n" ); document.write( " $\"+x+=+40+\"$
\n" ); document.write( "It could not have been 40 yrs ago- The man wasn't born yet.
\n" ); document.write( "It must have been 5 years ago
\n" ); document.write( "check the answer:
\n" ); document.write( " $\"+%28+37+-+x+%29%2A%28+8+-+x+%29+=+96+\"$
\n" ); document.write( " $\"+%28+37+-+5+%29%2A%28+8+-+5+%29+=+96+\"$
\n" ); document.write( " $\"+32%2A3+=+96+\"$
\n" ); document.write( " $\"+96+=+96+\"$
\n" ); document.write( "OK \n" ); document.write( "

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