document.write( "Question 197183: Shad is 3 ft. from a lamppost that is 12 ft. high. If Shad is 5 1/2 ft. tall, How long is Shad's shadow? \n" ); document.write( "
Algebra.Com's Answer #147825 by RAY100(1637)![]() ![]() ![]() You can put this solution on YOUR website! A rough sketch helps to visualize. \n" ); document.write( ". \n" ); document.write( "Large rt triangle, square corner on right, height an right is 12, other leg, horizontal, is x. \n" ); document.write( ". \n" ); document.write( "Smaller triangle is drawn inside , with height 5.5.,,,horizontal leg is (x-3). \n" ); document.write( ". \n" ); document.write( "horizontal difference between heights is 3 \n" ); document.write( ". \n" ); document.write( "Problem is proportional triangles, one 12 height by (x) leg,,,other 5.5 high,,(x-3) leg \n" ); document.write( ". \n" ); document.write( "12/x = 5.5 / (x-3) \n" ); document.write( ". \n" ); document.write( "cross multiply \n" ); document.write( ". \n" ); document.write( "12x -36 =5.5 x \n" ); document.write( ". \n" ); document.write( "6.5 x = 36 \n" ); document.write( ". \n" ); document.write( "x=5.54,,,,lamppost shadow lg \n" ); document.write( ". \n" ); document.write( "Therefore Shad's shadow lg = (x-3) = 2.54 \n" ); document.write( ". \n" ); document.write( "checking \n" ); document.write( ". \n" ); document.write( "12/5.54 = 5.5 /2.54,,,,,ok \n" ); document.write( " |