document.write( "Question 977076: Find the number of pairs of natural number a and b which satisfy 1/a + 2/b = 1/18 where b is an odd natural number less than 80 ?? \n" ); document.write( "
Algebra.Com's Answer #598616 by ankor@dixie-net.com(22740)\"\" \"About 
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Find the number of pairs of natural number a and b which satisfy 1/a + 2/b = 1/18 where b is an odd natural number less than 80 ??
\n" ); document.write( "\"1%2Fa\" + \"2%2Fb\" = \"1%2F18\"
\n" ); document.write( "multiply equation by 18ab, cancel the denominators, we have
\n" ); document.write( "18b + 36a = ab
\n" ); document.write( "18b - ab = -36a
\n" ); document.write( "Factor out b
\n" ); document.write( "b(18-a) = -36a
\n" ); document.write( "b = \"%28-%2836a%29%29%2F%28%2818-a%29%29\" = \"%28-%2836a%29%29%2F%28-1%28a-18%29%29\"
\n" ); document.write( "b = \"%2836a%29%2F%28a-18%29\"
\n" ); document.write( ":
\n" ); document.write( "I don't think there are any pairs of natural numbers (meaning positive integers) that satisfy this.
\n" ); document.write( "A graph of the above equation shows this
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+%2836x%29%2F%28x-18%29%29+\"
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