document.write( "Question 1005505: Solve the logarithmic equation showing step by step. log2(x^2-11)-log2(2x+5)=1 \n" ); document.write( "

Algebra.Com's Answer #621741 by Timnewman(323) $\"\"$ $\"About$

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Hi dear,
\n" ); document.write( "Follow the step below.
\n" ); document.write( " log2(x²-11)-log2(2x+5)=1
\n" ); document.write( "Then,
\n" ); document.write( "apply law of logarith.
\n" ); document.write( "log2[(x²-11)/(2x+5)]=1
\n" ); document.write( "but
\n" ); document.write( "log2[(x²-11)/(2x+5)=log2 base 2
\n" ); document.write( "cancel log from bothside,
\n" ); document.write( "(x²-11)/(2x+5)=2
\n" ); document.write( "Then,simplify out,
\n" ); document.write( "x²-11=2(2x+5)
\n" ); document.write( "x²-11=4x+10
\n" ); document.write( "x²-4x-21=0
\n" ); document.write( "factorize,
\n" ); document.write( "(x²-7x)+(3x-21)=0
\n" ); document.write( "x(x-7)+3(x-7)=0
\n" ); document.write( "(x+3)(x-7)=0
\n" ); document.write( "x+3=0 or x-7=0
\n" ); document.write( "x=-3 or x=7
\n" ); document.write( "Therefore the value of x is -3 or 7.
\n" ); document.write( "HOPE THIS HELPS?
\n" ); document.write( "::TIMNEWMAN:: \n" ); document.write( "

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