document.write( "Question 101751This question is from textbook Precalculus with Limits
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document.write( "(2z+3)^(2/3) + (2z+3)^(1/3) = 6\r
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document.write( "We've tried cubing each side which gets rather complicated, and we've tried factoring out a (2z+3)^(1/3), but we're not making any progress. Dad is helping, but he's having a tough time remembering complex radical problems! \n" );
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Algebra.Com's Answer #73986 by bucky(2189)![]() ![]() ![]() You can put this solution on YOUR website! Interesting problem. You can make the problem a little easier to work by making the following \n" ); document.write( "substitution: let \n" ); document.write( ". \n" ); document.write( "When you make that substitution the problem becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Get this into the standard quadratic form by subtracting 6 from both sides. When you do that \n" ); document.write( "the equation becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "This equation can be solved by factoring. When factored you get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "This can be solved for A by setting each of the factors equal to zero, which is one technique \n" ); document.write( "for solving a quadratic equation that can be factored. Setting each of the factors equal \n" ); document.write( "to zero results in: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and in: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "So there are two answers for A. And at this time we can return to the original definition \n" ); document.write( "of A and substituting \n" ); document.write( "we do we get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Cube both sides of this to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Subtract 3 from both sides and you get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and solve for z by dividing both sides by 2 to find that: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "You can next use that same process on the second answer that you got for A, which was \n" ); document.write( "A = 2. Substitute \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Cube both sides and you have: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Subtract 3 from both sides to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Divide both sides by 2 and you get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "So you have two answers for z ... \n" ); document.write( ". \n" ); document.write( "Hope this helps you to see how you can get answers for z. \n" ); document.write( " |