Answer:
Story
Jane is 1.7 m tall. She stands 250 m away from the base of the Eiffel tower and looks up at the top of the building. The angle of elevation from her eyeline to the top of the building is 45°.
Question
Calculate an estimate of the height of the building. Give your answer to the nearest meter.
Calculation
Label the sides of the triangle O, A and H (where O is the side opposite to the angle, A is the side adjacent to the angle and H is the hypotenuse).
In the triangle, the angle and side A is known, and O must be calculated.
Therefore, use the trig ratio tan(x) = O/A:
⇒ tan(40) = O/250
⇒ 250tan(40) = O
⇒ O = 209.7749078...
Assume Jane's eye-level is approximately 1.5 m above the ground.
Therefore, the Eiffel tower is approximately:
209.7749078... + 1.5 = 211.2749078.. meters tall
Rounding to the nearest meter ⇒ 211 m