Question

angle B of triangle ABC is an acute angle and AD perpendicular BC prove that AC2 =AB2+BC2-2BC-BD2​

Answer 1

Answer:

ANSWER

Since triangles ABd and ACD are right angled at D.

Therefore, AB

2

=AD

2

+BD

2

......................1

And, AC

2

=AD

2

+CD

2

........................2

Subtracting 2 from 1 we get

AB

2

−AC

2

=BD

2

−CD

2