triangle ABC is a right angled triangle at C. If D is mid point of bc then prove that ; AB2 =4AD2-3AC2
sakshi saini
11 Years agoGrade
2 Answers
kaushik kashyap
11 Years ago
look sakshi, please solve this problem by drawing a neat diagram. it is given that triangle ABC is a right angled triangle right angled at C and D is the mid point of bc . by applying pythagoras theorem in triangle ABC , we get AB2=AC2+BC2 =AC2+(2CD)2 (SINCE D IS THE MID POINT OF BC) =AC2+4CD2 =AC2+4(AD2_AC2) ( SINCE IN TRIANGLE ACD WE GET AD2=AC2+CD2) =AC2+4AD2_4AC2 =4AD2_3AC2 THEREFORE , AB2=4AD2_3AC2. THANK YOU . KAUSHIK.
Yash Chourasiya
5 Years ago
Dear Student
From right triangle ACB, By Pythagoras Theoremwe have, AB2= AC2+ BC2 AB2= AC2+ (2CD)2[since BC = 2CD] AB2= AC2+ 4CD2 AB2= AC2+ 4(AD2- AC2) [From right △ACD] AB2= 4AD2- 3AC2. Hence Proved
I hope this answer will help you. Thanks & Regards Yash Chourasiya