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3 years ago

In triangle $DEF,$ $\angle D = 30^\circ,$ $\angle F = 60^\circ,$ and $EF = 6.$ Find $DE + DF.$

Mathematics

1 answer:

tia_tia [17]3 years ago

6 0

Answer:

22.39

Step-by-step explanation:

angle D + angle F + angle E = 180 (angle of triangle)

30 +60 + E = 180

E = 180 - 90

E = 90

so triangle DEF is right angled triangle

we know that,

sin 30 = EF /DF

OR, 1/2 = 6/ DF

OR, DF= 12

again,

cos 30 = De/DF

root3 /2 = DE /12

DE= 10.39

hence DF +DE

= 12 + 10.39

= 22. 39

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Harlamova29_29 [7]

Answer:

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Explanation -

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2/3 p + 10 = 22

2/3 p = 22- 10

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Answer:

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Step-by-step explanation:

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Step-by-step explanation:

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