How is this 90 degrees?

  • Thread starter Joza
  • Start date
  • #1
139
0
http://www.e-xamit.ie/2005test/php/GetDocByID.php?id=562&prep=565&soln=562&tip=570&port=566 [Broken]


I can't figure out how it takes the angle dec to be 90 degrees? How?
 
Last edited by a moderator:

Answers and Replies

  • #2
arildno
Science Advisor
Homework Helper
Gold Member
Dearly Missed
10,025
134
Line segment ce is parallell to line segment ab. Line segment ad is perpendicular to ab at a, hence, ad is perpindicular to ec at e.
 

Related Threads on How is this 90 degrees?

Replies
5
Views
2K
  • Last Post
Replies
3
Views
3K
Replies
5
Views
1K
  • Last Post
Replies
4
Views
1K
Replies
8
Views
2K
  • Last Post
Replies
8
Views
780
  • Last Post
Replies
7
Views
2K
Replies
14
Views
4K
Top