document.write( "Question 481494: A semielliptic archway has a height of 20 feet and a width of 50 feet, can a truck 14 feet high and 10 feet wide drive under the archway without going into the other lane? \n" ); document.write( "
Algebra.Com's Answer #329969 by lwsshak3(11628)![]() ![]() ![]() You can put this solution on YOUR website! A semielliptic archway has a height of 20 feet and a width of 50 feet, can a truck 14 feet high and 10 feet wide drive under the archway without going into the other lane? \n" ); document.write( "** \n" ); document.write( "Draw an ellipse with a horizontal major axis of the standard form: \n" ); document.write( "(x-h)^2/a^2+(y-k)^2/b^2=1 \n" ); document.write( "Place the center of this ellipse at the origin (0,0). \n" ); document.write( "The equation now becomes: x^2/a^2+y^2/b^2=1 \n" ); document.write( "The given width of the semielliptic archway of 50 feet represents the major axis=2a \n" ); document.write( "a=25 \n" ); document.write( "a^2=625 \n" ); document.write( "The given height of the semielliptic archway of 20 feet represents half of the major axis=b \n" ); document.write( "b=20 \n" ); document.write( "b^2=400 \n" ); document.write( ".. \n" ); document.write( "Equation of the ellipse: \n" ); document.write( "x^2/625+y^2/400=1 \n" ); document.write( "The top half of this ellipse represents the semielliptic archway. \n" ); document.write( ",.. \n" ); document.write( "Determine whether a truck 14 feet high and 10 feet wide can drive under the archway without going into the other lane? \n" ); document.write( ".. \n" ); document.write( "Plug y=14 ft (height of truck) into the equation and solve for x (allowable width of archway). \n" ); document.write( "x^2/625+14^2/400=1 \n" ); document.write( "x^2/625+196/400=1 \n" ); document.write( "x^2=(1-196/400)*625=318.75 \n" ); document.write( "Taking the positive sqrt because using upper half of ellipse \n" ); document.write( "x=√318.75=17.85 ft \n" ); document.write( "This means that at the height clearance of 14 ft, there is more than 17 ft of road width allowed for the 10 ft wide truck. \n" ); document.write( "ans: \n" ); document.write( "So, the archway can easily accommodate the 14 ft high and 10 ft wide truck. \n" ); document.write( " |