document.write( "Question 1067008: x+1 2-x
\n" ); document.write( "5 +5 =126 \n" ); document.write( "

Algebra.Com's Answer #682233 by Alan3354(69443) $\"\"$ $\"About$

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5^(x+1) + 5^(2-x) = 126
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\n" ); document.write( "Check for an integer solution first.
\n" ); document.write( "5 to the power of a positive integer is a multiply of 5.
\n" ); document.write( "--> For the sum to be 126, one of the terms has to be 1.
\n" ); document.write( "5^0 = 1
\n" ); document.write( "Either x+1 = 0
\n" ); document.write( "--> x = -1
\n" ); document.write( "That doesn't work.
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\n" ); document.write( "Or 2-x = x
\n" ); document.write( "--> x = 2
\n" ); document.write( "That works.
\n" ); document.write( "5^3 + 5^0 = 126
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\n" ); document.write( "If it had been 5^(x+1) + 5^(2-x) = 127, there would be no algebraic solution, only numerical methods.
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