document.write( "Question 198521: The altitude of a triangle is 3/4 the length of its base. If the altitude were increased by 3 feet and the base decreased by 3 feet, the area would be unchanged. Find the length of the base and altitude. \n" ); document.write( "
Algebra.Com's Answer #149043 by nerdybill(7384) You can put this solution on YOUR website! The altitude of a triangle is 3/4 the length of its base. If the altitude were increased by 3 feet and the base decreased by 3 feet, the area would be unchanged. Find the length of the base and altitude. \n" ); document.write( ". \n" ); document.write( "Original triangle: \n" ); document.write( "Let b = length of base \n" ); document.write( "then \n" ); document.write( "(3/4)b = altitude \n" ); document.write( "Area = (1/2)b(3/4)b = (3/8)b^2 \n" ); document.write( ". \n" ); document.write( "Changed triangle: \n" ); document.write( "b-3 = length of base \n" ); document.write( "(3/4)b+3 = altitude \n" ); document.write( "Area = (1/2)(b-3)(3/4)b+3 = (3/8)(b-3)b+3 \n" ); document.write( ". \n" ); document.write( "Set area equal to each other: \n" ); document.write( "(3/8)b^2 = (3/8)(b-3)b+3 \n" ); document.write( "b^2 = (b-3)b+3 \n" ); document.write( "b^2 = b^2-3b+3 \n" ); document.write( "0 = -3b+3 \n" ); document.write( "-3 = -3b \n" ); document.write( "1 feet = b (base of triangle) \n" ); document.write( ". \n" ); document.write( "Altitude: \n" ); document.write( "(3/4)b = (3/4)1 = 3/4 feet (altitude)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |