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In triangle DEF, angle D = 30º, angle F = 60º, and EF = 6. Find DE + DF. 

any help is appreciated. tysm!!!

 Dec 24, 2020
edited by skc123  Dec 24, 2020
 #1
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We have a 30-60-90  right triangle

 

You  should memorize  these relationships in a  a 30-60-90  triangle

 

30          60              90

x      x* sqrt (3)        2x

 

The  angle opposite  the 30° angle  =  x =   6

 

The  angle opp  the  60°  = x* sqrt (3)  =   6*sqrt (3)  = DE

 

The angle opp the 90° angle  = 2x  =   2 (6)    =12  = DF

 

So

 

DE + DF  = 

 

6sqrt (3)  + 12

 

 

cool cool cool

 Dec 24, 2020
 #2
avatar+31 
0

tysm for you help!

 Dec 24, 2020

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