document.write( "Question 747238: I really need help with the statement and reason of this problem.\r
\n" ); document.write( "\n" ); document.write( "Given: Line segment BD bisects angle ABC
\n" ); document.write( " Angle BAD is congruent to angle BCD
\n" ); document.write( "Prove: Triangle ADC is isosceles\r
\n" ); document.write( "\n" ); document.write( "So far I have this:
\n" ); document.write( "1. Line segment BD bisects angle ABC
\n" ); document.write( "Reason: Given\r
\n" ); document.write( "\n" ); document.write( "2. Angle BAD is congruent to angle BCD
\n" ); document.write( "Reason: Given\r
\n" ); document.write( "\n" ); document.write( "3. Line segment AB is congruent to line segment CB
\n" ); document.write( "Reason ?\r
\n" ); document.write( "\n" ); document.write( "4.Triangle ABC is isosceles
\n" ); document.write( "Reason: Def of isosceles triangle\r
\n" ); document.write( "\n" ); document.write( "5. Triangle ADC is isosceles
\n" ); document.write( "Reason: Triangle ABC is isosceles which makes triangle ADC isosceles; Def of isosceles triangle \r
\n" ); document.write( "\n" ); document.write( "I am really unsure about this problem as it just does not see correct but I do not understand how to make it correct.
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Algebra.Com's Answer #454779 by timvanswearingen(106)\"\" \"About 
You can put this solution on YOUR website!
I believe the reason you're looking for on step 3 is the isosceles triangle theorem. \r
\n" ); document.write( "\n" ); document.write( "Since angle BAD is congruent to angle BCD, the sides opposite those angles in triangle ABC are congruent. \r
\n" ); document.write( "\n" ); document.write( "Thus, AB is congruent to CB. \r
\n" ); document.write( "\n" ); document.write( "Assuming this problem looks like a kite, after step 4,\r
\n" ); document.write( "\n" ); document.write( "5. let E be the point of intersection between AC and BD. \r
\n" ); document.write( "\n" ); document.write( "6. you need to show that triangle ABE is congruent to triangle CBE using ASA (angle side angle). \r
\n" ); document.write( "\n" ); document.write( "7. Then AE is congruent to CE by CPCTC. (corresponding parts of congruent triangles are congruent.)\r
\n" ); document.write( "\n" ); document.write( "8. Also, angle AEB is congruent to angle CEB by CPCTC \r
\n" ); document.write( "\n" ); document.write( "9. Angle CEB is congruent to angle AED and angle AEB is congruent to angle CED (vertical angles)\r
\n" ); document.write( "\n" ); document.write( "10. Thus, angle AED is congruent to angle CED (transitive)\r
\n" ); document.write( "\n" ); document.write( "11. ED is congruent to ED (reflexive)\r
\n" ); document.write( "\n" ); document.write( "12. By SAS (side angle side) triangle AED is congruent to triangle CED.\r
\n" ); document.write( "\n" ); document.write( "13. AD is congruent to CD by CPCTC.\r
\n" ); document.write( "\n" ); document.write( "14. Thus, triangle ADC is isosceles by the definition of an isosceles triangle.
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