document.write( "Question 166492: please help me solve this problem.\r
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document.write( "the area of a triangle is 13.5 meters. Find the base and height of the retangle
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document.write( "if its height is 6 meters greaster than it's base. Use an equation and the formula area of a triangle =0.5(base)(height). \n" );
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Algebra.Com's Answer #122697 by gonzo(654)![]() ![]() ![]() You can put this solution on YOUR website! A = (b*h)/2 (equation 1) \n" ); document.write( "where A = area \n" ); document.write( "b = base \n" ); document.write( "h = height \n" ); document.write( "----- \n" ); document.write( "h = b+6 (given) \n" ); document.write( "A = 13.5 (given) \n" ); document.write( "equation 1 becomes: \n" ); document.write( "A = [b*(b+6)]/2 = 13.5 \n" ); document.write( "which becomes: \n" ); document.write( "[b*(b+6)]/2 = 13.5 (equation 2) \n" ); document.write( "----- \n" ); document.write( "multiply both sides of equation 2 by 2: \n" ); document.write( "b*(b+6) = 27 \n" ); document.write( "simplify: \n" ); document.write( "b^2 + 6*b = 27 \n" ); document.write( "complete the squares: \n" ); document.write( "(b+3)^2 = 27 + 9 (explanation for this down below after the answer) \n" ); document.write( "simplify: \n" ); document.write( "(b+3)^2 = 36 \n" ); document.write( "take square root of both sides: \n" ); document.write( "b+3 = +/- 6 \n" ); document.write( "subtract 3 from both sides: \n" ); document.write( "b = +/- 6 - 3 \n" ); document.write( "b becomes either: \n" ); document.write( "6-3 = 3 \n" ); document.write( "or: \n" ); document.write( "-6-3 = -9 \n" ); document.write( "----- \n" ); document.write( "since b can't be negative, answer has to be: \n" ); document.write( "b = 3 \n" ); document.write( "----- \n" ); document.write( "since h = b+6, then: \n" ); document.write( "h = 9 \n" ); document.write( "----- \n" ); document.write( "you have: \n" ); document.write( "b = 3 \n" ); document.write( "h = 9 \n" ); document.write( "A = 13.5 (given) \n" ); document.write( "----- \n" ); document.write( "substitute in equation 1: \n" ); document.write( "A = (b*h)/2 (equation 1) \n" ); document.write( "A = (3*9)/2 = 13.5 \n" ); document.write( "A = 27/2 = 13.5 \n" ); document.write( "A = 13.5 = 13.5 \n" ); document.write( "----- \n" ); document.write( "values for b and h prove out. \n" ); document.write( "equation is good. \n" ); document.write( "b = 3 \n" ); document.write( "h = 9 \n" ); document.write( "----- \n" ); document.write( "explanation for completing the squares is shown below: \n" ); document.write( "also shown below is the fact that you could have also solved this using the quadratic formula. \n" ); document.write( "----- \n" ); document.write( "in order to complete the squares of your equation: \n" ); document.write( "b^2 + 6*b) \n" ); document.write( "i took half of the 6 and turned the equation into: \n" ); document.write( "(b+3)^2 \n" ); document.write( "if you multiply this out, you will get: \n" ); document.write( "b^2 + 6*b + 9 \n" ); document.write( "there's an extra 9 in there. \n" ); document.write( "in order to keep the equations in balance i had to add 9 to the other side of the equation. \n" ); document.write( "that's why the equation went from: \n" ); document.write( "b^2 + 6*b = 27 \n" ); document.write( "to: \n" ); document.write( "(b+3)^2 = 27 + 9 \n" ); document.write( "the additional 9 on the right hand side of the equation kept them in balance because i added 9 to the left hand side by completing the squares. \n" ); document.write( "----- \n" ); document.write( "use of the quadratic formula instead. \n" ); document.write( "----- \n" ); document.write( "rather than completing the squares, you can also solve this equation using the quadratic formula. \n" ); document.write( "the equation to solve was: \n" ); document.write( "b^2 + 6*b = 27 \n" ); document.write( "subtract 27 from both sides of the equation: \n" ); document.write( "b^2 + 6*b - 27 = 0 \n" ); document.write( "let x = b (this is necessary because general form of quadratic equation and quadratic formula use b for another purpose) \n" ); document.write( "----- \n" ); document.write( "formula becomes: \n" ); document.write( "x^2 + 6*x - 27 = 0 \n" ); document.write( "general form of quadratic equation is: \n" ); document.write( "a*x^2 + b*x + c = 0 \n" ); document.write( "the quadratic formula can be used to solve this quadratic equation. \n" ); document.write( "general form of quadratic formula is: x = \n" ); document.write( "a = 1 \n" ); document.write( "b = 6 \n" ); document.write( "c = -27 \n" ); document.write( "----- \n" ); document.write( "b^2 = 36 \n" ); document.write( "4*a*c = -108 \n" ); document.write( "2*a = 2 \n" ); document.write( "----- \n" ); document.write( "quadratic formula becomes \n" ); document.write( "x = \n" ); document.write( "this becomes: \n" ); document.write( "x = (-6 +/- 12)/2 \n" ); document.write( "which becomes \n" ); document.write( "x = 6/2 = 3 \n" ); document.write( "or: \n" ); document.write( "x = -18/2 = -9 \n" ); document.write( "----- \n" ); document.write( "the answers are the same. \n" ); document.write( "you could solve by completing the square or you could solve by quadratic formula, whichever is easiest for you. \n" ); document.write( "-----\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |