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a guy wire makes a 67 degree angle with the ground. walking out 32 ft further grom the tower,the angle of elevation to the top of the tower is 39 degrees. find the height of the tower

User Silwar
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1 Answer

2 votes

Answer:

39.5 ft

Explanation:

The mnemonic SOH CAH TOA reminds you of the relation between angles and sides of a right triangle.

Tan = Opposite/Adjacent

This lets us write two equations in two unknowns:

tan(67°) = AD/CD . . . . . . . . . . angle at guy point

tan(39°) = AD/(CD+32) . . . . . .angle 32' farther

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Solving the first equation for CD and using that in the second equation, we can get an equation for AD, the height of the tower.

CD = AD/tan(67°)

tan(39°)(CD +32) = AD . . . . eliminate fractions in the second equation

tan(39°)(AD/tan(67°) +32) = AD

32·tan(39°) = AD(1 -tan(39°)/tan(67°)) . . . simplify, subtract left-side AD term

32·tan(39°)tan(67°)/(tan(67°) -tan(39°)) = AD . . . . divide by AD coefficient

AD ≈ 39.486 . . . . feet

The tower is about 39.5 feet high.

a guy wire makes a 67 degree angle with the ground. walking out 32 ft further grom-example-1
User Starikovs
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