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As shown in the diagram below, a building casts a72-foot shadow on the ground when the angle ofelevation of the Sun is 40°.588BEBB140°-72 ftHow tall is the building, to the nearest foot?

As shown in the diagram below, a building casts a72-foot shadow on the ground when-example-1
User Simon Josef Kok
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1 Answer

15 votes
15 votes

EXPLANATION

Shadow=72 foot

The tall can be obtained by pplying the Pythagorean Theorem as shown as follows:


\tan \theta=\frac{Opposite\text{ Cathethus}}{\text{Adjacent cathetus}}

As we can see, theta = 40 degrees, Opposite= unknown, Adjacent=72 ft

Replacing terms:


\tan 40=\frac{\text{unknown }}{72}

Multiplying both sides by 72:


72\cdot\tan 40=unknown

Solving the trig.:


72\cdot0.84=\text{unknown}

Multiplying numbers:


60.48\text{ = unknown}

Switching sides:


\text{unknown = 60.48}

Answer: the building is 60 feet tall

User Beep Beep
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