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 o
f the tower is 39 degrees. find the height of the tower
1 answer:
Answer:
39.5 ft
Step-by-step 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.
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