Help with Triangle

Merida

New member
Joined
Nov 4, 2020
Messages
31
I have attached the question , solution and my working . I need help to understand how a small part of the answer was derived
I want to know how the third vertex of the triangle was found
 

Attachments

  • AF31C03D-C129-4BAD-918A-F2528AFB0C40.jpeg
    AF31C03D-C129-4BAD-918A-F2528AFB0C40.jpeg
    640.4 KB · Views: 19
  • CDAAB6FA-529D-4FC3-A441-6EDE0AA984F4.jpeg
    CDAAB6FA-529D-4FC3-A441-6EDE0AA984F4.jpeg
    618.9 KB · Views: 17
Top