document.write( "Question 886057: What is x in log base 5 (x+1) + log base 5(x+21) =3 \n" ); document.write( "

Algebra.Com's Answer #535625 by lwsshak3(11628) $\"\"$ $\"About$

You can put this solution on YOUR website!
What is x in log base 5 (x+1) + log base 5(x+21) =3
\n" ); document.write( " $\"log%285%2C%28x%2B1%29%29%2Blog%285%2C%28x%2B21%29%29=3\"$
\n" ); document.write( " $\"log%285%2C%28%28x%2B1%29%28x%2B21%29%29%29=3\"$
\n" ); document.write( "(x+1)(x+21)=5^3=125
\n" ); document.write( "x^2+22x+441=125
\n" ); document.write( "x^2+22x+316=0
\n" ); document.write( "solve for x by 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, b=22, c=316
\n" ); document.write( "no real solution:
\n" ); document.write( "b^2-4ac<0 \n" ); document.write( "

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