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D) The shadow of a vertical tower on a level ground increases by 10m, when the altitude of sum changes from angle of elevation 45° to 30°. Find the height of the towe correct to one place of decimal. (Take root 3 = 1.732)​

Help As soon as possible please with picture please

1 Answer

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Answer:

Below.

Explanation:

I cant draw you a picture but it will be one right triangle inside the other where the vertical tower will be one leg common to 2 triangles and the base of the 2 triangles will be x and x+10 metres.

Tan 30 = h/ (x + 10)

tan 45 = h/x where h is the height of the tower.

From the second equation x = h / tan45

Substituting in the first equation;

tan30 = h / (h/tan45 + 10

Tan 30 = 1/ √3 and tan 45 = 1 so

1/ 1.732 = h/ (h + 10)

0.5774 = h/(h + 10)

h = 0.5774h + 57.74

0.4226 h = 57.74

h = 136.6 m to nearest tenth.

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