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Given \triangle DEF△DEF triangle, D, E, F, find DE

Round your answer to the nearest hundredth.

User Dbrasco
by
2.8k points

2 Answers

3 votes

Answer:

x ≈ 36.09

correct on khan

Explanation:

User Jvm
by
2.9k points
1 vote

Answer:

x ≈ 36.09

Explanation:

Complete question

Use △DEF, shown below, to answer the question that follows: Triangle DEF where angle E is a right angle. DE measures x. DF measures 55. Angle D measures 49 degrees. What is the value of x rounded to the nearest hundredth? Type the numeric answer only in the box below.

According to the diagram

m<E = 90 degrees

m<D = 49 degrees

DF = 55 = hypotenuse

DE = x = adjacent

EF = opposite

According to SOH CAH TOA identity;

Cos theta = adj/hyp

Cos m<D = DE/DF

Cos 49 = x/55

x = 55cos49

x = 55(0.6561)

x = 36.0855

x ≈ 36.09 (to the nearest hundredth)

User Nussjustin
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3.1k points