document.write( "Question 1208873: In the triangle shown below, DB = DC, DE=CE and
Algebra.Com's Answer #847378 by greenestamps(13203) You can put this solution on YOUR website! \n" ); document.write( "Strategy: \n" ); document.write( "(1) Use the given congruent line segments to define variables for the measures of the two pairs of congruent angles in triangles BDC and EDC \n" ); document.write( "(2) Use those variables to find expressions for the measures of all the other angles in the figure (note some of these will not be used in solving the problem) \n" ); document.write( "(3) BC and DE are parallel, so angles CBD and EDA are congruent. Use the expressions for the measures of those two angles to solve the problem \n" ); document.write( "DB = DC, so angles DBC and DCB are congruent. Let x be the measure of each of those two angles. That makes the measure of angle BDC 180-2x. \n" ); document.write( "DE = CE, so angles ECD and EDC are congruent. Let y be the measure of each of those two angles. \n" ); document.write( "The sum of the measures of angles BDC, CDE, and EDA is 180 degrees, so the measure of angle EDA is 2x-y. \n" ); document.write( "DE is parallel to BC, so angles CBD and EDA are congruent. So \n" ); document.write( "x = 2x-y --> y = x. \n" ); document.write( "In triangle ABC, the sum of the measures of the angles is 180 degrees: \n" ); document.write( "x + (x+y) + 48 = 180 \n" ); document.write( "x + (x+x) = 132 \n" ); document.write( "3x = 132 \n" ); document.write( "x = 44 \n" ); document.write( "The measure of angle ACB is x+y = 2x = 88. \n" ); document.write( "ANSWER: 88 degrees \n" ); document.write( " \n" ); document.write( " |