document.write( "Question 252705: determine the vertex of quadratic function stating axis of symmetry,minimum or maximum value,and domain and range on y=10x^2+5x-1
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document.write( "and y=-24x^2+18x+11
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document.write( "I am not understanding even though i read over examples. \n" );
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Algebra.Com's Answer #184759 by drk(1908)![]() ![]() ![]() You can put this solution on YOUR website! let's start with the first equation and then move to the second: \n" ); document.write( " \n" ); document.write( "quadratics are expressed as Y = Ax^2 + Bx + C. \n" ); document.write( "-- \n" ); document.write( "vertex: \n" ); document.write( "We can find the vertex using -b/2a. -5/2*10 = -5/20 = -1/4. This is the x part of the vertex and now we put that into f(x) to get \n" ); document.write( "10(1/4)^2 + 5(1/4)-1 = 10/16 + 5/4 - 1 = 14/16 = 7/8. \n" ); document.write( "vertex = (1/4,7/8) \n" ); document.write( "-- \n" ); document.write( "axis of symmetry: \n" ); document.write( "This is just the x value of the vertex \n" ); document.write( "x = 1/4. \n" ); document.write( "-- \n" ); document.write( "min: \n" ); document.write( "since the graph opens up, there will be a min at the vertex. \n" ); document.write( "min @ (1/4,7/8) \n" ); document.write( "-- \n" ); document.write( "domain:domain: For a parabola opening up or down, domain will be all reals. \n" ); document.write( "range: Since the parabola opens up, the minimum range is 7/8. So we have Y >= 7/8.\r \n" ); document.write( "\n" ); document.write( "-- EQUATION #2 \n" ); document.write( "{{y = -24x^2 + 18x + 11}} \n" ); document.write( "quadratics are expressed as Y = Ax^2 + Bx + C. \n" ); document.write( "-- \n" ); document.write( "vertex: \n" ); document.write( "We can find the vertex using -b/2a. -18/2*-24 = 18/48 = 3/8. This is the x part of the vertex and now we put that into f(x) to get \n" ); document.write( "-24(3/8)^2 + 18(3/8) + 11 = -27/8 + 27/4 + 11 = 115/4. \n" ); document.write( "vertex = (3/8, 115/4) \n" ); document.write( "-- \n" ); document.write( "axis of symmetry: \n" ); document.write( "This is just the x value of the vertex \n" ); document.write( "x = 3/8. \n" ); document.write( "-- \n" ); document.write( "min: No min in this case.\r \n" ); document.write( "\n" ); document.write( "max: SInce the graph opens down, there will be a max at the vertex. \n" ); document.write( "min @ (3/8, 115/4) \n" ); document.write( "-- \n" ); document.write( "domain: For a parabola opening up or down, domain will be all reals. \n" ); document.write( "range: Since the parabola opens down, the highest range is 115/4. So we have Y <= 115/4. \n" ); document.write( " |