1. how to provea angle  is a angle os a 90 degree? 

                              
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Asked by sanatanblue | 28th Dec, 2015, 10:19: AM

Expert Answer:

 
S t e p 1 colon D r a w space a space s t r a i g h t space l i n e space A B space a n d space e x t e n d space i t space t o space m a r k space t h e space l i n e space L S t e p 2 colon M a r k space t h e space p o i n t space O comma space t h e space v e r t e x space o f space t h e space a n g l e comma space o n space t h e space l i n e space L. S t e p 3 colon P l a c e space t h e space p r o t r a c t o r space o v e r space t h e space g i v e n space l i n e space L space s u c h space t h a t space t h e space l i n e space L space c o i n c i d e s space w i t h space t h e space b a s e space l i n e space o f space t h e space p r o t r a c t o r. S t e p 4 colon S i n c e space t h e space g i v e n space a n g l e space i s space 90 space d e g r e e s comma space m a r k space w i t h space t h e space p e n c i l space w h e r e space t h e space m a r k space i n space t h e space p r o t r a c t o r space s h o w s space 90 space d e g r e e s S t e p 5 colon J o i n space t h e space p o i n t s space O space a n d space P space a n d space e x t e n d space t h e space l i n e space M. N o w space angle B O P equals angle A O P equals 90 degree

Answered by Vimala Ramamurthy | 29th Dec, 2015, 08:56: AM