Help needed

[Merida]

I am not able to figure out just one part of the solution
How is the third vertex of the equilateral triangle obtained
I have marked my query in my working

 

[Dr.Peterson]

One way to find the third vertex of an equilateral triangle is to locate the midpoint of the known side, and add to its location vector a vector perpendicular to the side and with length [MATH]\sqrt{3}[/MATH] times as long as the vector to the midpoint.

If that doesn't work for you, please show us what you have tried, and what you have learned that you can use.

 

[Merida]

thanks but I didn’t understand what you asked me to do . If you could please explain a little more clearly , it would be great help
If I knew how to find out or had learned how to do it , I wouldn’t have asked . I ve been sitting with that , trying to figure out that one step for days now

 

[Dr.Peterson]

thanks but I didn’t understand what you asked me to do . If you could please explain a little more clearly , it would be great help
If I knew how to find out or had learned how to do it , I wouldn’t have asked . I ve been sitting with that , trying to figure out that one step for days now

Please give us some indication of what you know and what you don't, so we can direct our help at your specific needs. I intentionally gave minimal suggestions, expecting you to say something like "I don't know about vectors" or "I understand why [MATH]\sqrt{3}[/MATH] would be involved in an equilateral triangle, but how do I do this?", or something! Telling us specifically what you don't understand is far more helpful to us than "please try again".