document.write( "Question 1120176: Given the quadratic function f(x) = 2x2– 8x + 11
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document.write( "Use “completing the squares” to convert the quadratic function into vertex form
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document.write( "State the vertex, Find the x- and y-intercepts, Graph the function\r
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document.write( "the end answer is 2(x-2)^2 +3, I need the steps in-between the problem and the answer \n" );
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Algebra.Com's Answer #735841 by greenestamps(13198)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "You might want to look at the lesson tutor @ikleyn suggested in her response. Completing the square is a skill you might need in a lot of different types of math problems. \n" ); document.write( "In case they might help your understanding of the process, let me add a few notes of explanation to the solution as she showed it.... \n" ); document.write( " \n" ); document.write( "Ignore the constant term for the moment; you need to complete the square in the variable x. \n" ); document.write( " \n" ); document.write( "To complete the square, you need to factor out the leading coefficient: \n" ); document.write( " \n" ); document.write( "Think of the pattern for squaring a binomial: (x+a)^2 = x^2+2ax+a^2. The coefficient of the middle term in the product is twice the constant term in the binomial. So to complete a square you need to take half the coefficient of the linear term and square it. \n" ); document.write( "In this example, the coefficient of the linear term is -4; half of that squared is (-2)^2 = 4. You need to complete the square in the parentheses by adding 4. \n" ); document.write( "Note that you have added 4 inside the parentheses, so you have added 2*4=8 to the expression as a whole. To balance that, you need to subtract 8 from the expression (outside of the parentheses). \n" ); document.write( " \n" ); document.write( "Now write the trinomial as a binomial squared, and simplify the rest of the expression. \n" ); document.write( " \n" ); document.write( "The square of a number is always 0 or positive, so the minimum value of the expression will be when (x-2) is zero -- i.e., when x=2. And the value of the expression when x=2 is 2(0^2)+3 = 3. So the vertex of the graph is (2,3). \n" ); document.write( " |