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A flag staff is fixed at one corner of a rectangular room of side 20×10m.The angle of elevation on the top of the flag from opposite corner of the room is found 30.Find the height is flag staff.

User Zsytssk
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1 Answer

7 votes

Answer:

The height is 12.9m

Explanation:

First we have to find the distance from the corner of the flag to the opposite corner, for this we will use Pythagoras

In a right-angled triangle, the square of the hypotenuse side is equal to the sum of squares of the other two sides

h² = s1² + s2²

h² = 10² + 20²

h² = 100 + 400

h² = 500

h = √500

h = 22.36

Now that we know this measurement we can calculate the height of the flagpole

well to start we have to know the relationship between angles, legs and the hypotenuse

α = 30

a: adjacent = 22.36

o: opposite = ?

h: hypotenuse

sin α = o/h

cos α= a/h

tan α = o/a

we see that it has (angle, adjacent, opposite)

is the tangent

tan α = o/a

tan 30 = o/22.36

tan30 * 22.36 = o

12.9 = o

The height is 12.9m

User Merni
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