Question

Δ ABC is an equilateral triangle. If point D is midpoint of side BC, then prove that 4 AD² = 3 BC²

Answer 1

Answer:

Hi..

Step-by-step explanation:

A very easy question..

Let abc be an equilateral triangle.

Now . d is the midpoint and AD is the altitude..

AD^2= AC^2- BD^2. ( Pythagoras theorem)

AD^2= AC^2- BC^2/4. ( bd= 1/2bc)

AD^2= 4ac^2-bc^2/4. ( lcm)

4ad^2= 4ac^2- ac^2. ( ac=bc)

4ad^2= 3 ac^2= 3bc^2

Hope you like it. Please mark as brainliest