document.write( "Question 668529: at a point on the ground 24ft from the base of a tree, the distance to the top of the tree if 4ft more than 3 times the height of the tree. Find the height of the tree. \n" ); document.write( "
Algebra.Com's Answer #415638 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! Let h = height of tree\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If \"at a point on the ground 24ft from the base of a tree, the distance to the top of the tree if 4ft more than 3 times the height of the tree\", then the distance is 3h+4 (and this is the hypotenuse while the other two values are the legs of a right triangle)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now use the Pythagorean theorem\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a^2 + b^2 = c^2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "24^2 + h^2 = (3h+4)^2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "576 + h^2 = 9h^2 + 24h + 16\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0 = 9h^2 + 24h + 16 - h^2 - 576\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0 = 8h^2 + 24h - 560\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "8h^2 + 24h - 560 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "8(h^2 + 3h - 70) = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "8(h+10)(h-7) = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "h+10 = 0 or h-7 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "h = -10 or h = 7\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Toss out the negative height (since it doesn't make sense) to get the only answer of h = 7\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the height of the tree is 7 ft. \n" ); document.write( " |