document.write( "Question 848415: two numbers have the sum of one and a sum of cubes 31. what is the product? \n" ); document.write( "
Algebra.Com's Answer #511068 by ankor@dixie-net.com(22740)\"\" \"About 
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two numbers have the sum of one
\n" ); document.write( "a + b = 1
\n" ); document.write( "a = (1-b)
\n" ); document.write( "and a sum of cubes 31.
\n" ); document.write( "a^3 + b^3 = 31
\n" ); document.write( "replace a with (1-b)
\n" ); document.write( "(1-b)^3 + b^3 = 31
\n" ); document.write( "FOIL (1-b)(1-b)(1-b) = 1 - 3b + 3b^2 - b^3
\n" ); document.write( "1 - 3b + 3b^2 - b^3 + b^3 = 31
\n" ); document.write( "a quadratic equation
\n" ); document.write( "3b^2 - 3b + 1 - 31 = 0
\n" ); document.write( "3b^2 - 3b - 30 = 0
\n" ); document.write( "using the quadratic formula, I got:
\n" ); document.write( "b = -2.70156212 then a = 3.70156212
\n" ); document.write( "or
\n" ); document.write( "b = 3.70156212 then a = -2.70156212
\n" ); document.write( ":
\n" ); document.write( "what is the product?
\n" ); document.write( "-2.70156212 * 3.70156212 = -10
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