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Need help trigonometry


Need help trigonometry ​-example-1
User Rybit
by
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1 Answer

2 votes

Answer:

The measure of angle F is 67.6°

Explanation:

In the right triangle DEF

∵ ∠E is the right angle

Side DF is opposite to ∠E

DF is the hypotenuse of the triangle DEF

∵ Side EF is the adjacent side of ∠F

∵ The cosine ratio =
(Adjacent)/(Hypotenuse)

cos∠F =
(EF)/(DF)

EF = 8 units

DF = 21 units

→ Substitute them in the cosine ratio above

cos∠F =
(8)/(21)

→ Use
cos^(-1) to find the measure of angle F

∵ m∠F =
cos^(-1)((8)/(21))

∴ m∠F = 67.60731219 degrees

→ Round it the nearest tenth of a degree

m∠F = 67.6°

The measure of angle F is 67.6°

User Mg Bhadurudeen
by
6.2k points