Two persons A and B are on the same side of a tower (T). Ifthe angles of elevation of the top of the tower as observed by A and B are 40°and 55° respectively and line /AB/ is 6m. Find the height of the tower.

Respuesta :

Answer:

Height of the tower is 12.07 meter.

Step-by-step explanation:

Given:

Angle of elevation observed from A = 40°

Angle of elevation from point B = 55°

Distance from A to B = 6 m

Note :

As we move towards the tower the angle of elevation will increase.

Let the height of the tower be "h'' meter.

And the distance from B to the base of the tower be "x'' m.

Adjacent length for angle 55° is ''x'' m and adjacent length from point A that is angle 40° is "6+x" m.

And we know that:

⇒ [tex]tan (\theta) = \frac{opposite}{adjacent}[/tex]

So arranging them in tangent angles.

⇒ [tex]tan(55) = \frac{h}{x}[/tex] Ā  Ā  Ā  Ā ...equation (i)

⇒ [tex]tan(40)=\frac{h}{x+6}[/tex] Ā  Ā ...equation (ii)

Dividing both the equation.

⇒ [tex]\frac{tan(55)}{tan(40)} =\frac{h}{x}\times \frac{6+x}{h}[/tex]

⇒ [tex]1.7=\frac{6+x}{x}[/tex]

⇒ [tex]1.7x=6+x[/tex]

⇒ [tex]1.7x-x=6[/tex]

⇒ [tex]0.7x=6[/tex]

⇒ [tex]x=\frac{6}{0.7}[/tex]

⇒ [tex]x=8.5[/tex] m

Now using the value of 'x' in equation (i).

⇒ [tex]h=x\times tan(55)[/tex] Ā 

⇒ [tex]h=8.5(1.42)[/tex]

⇒ [tex]h=12.07[/tex] m

Height of the tower is 12.07 meter.

Ver imagen jitushashi143

Answer:

12.2 meters

Step-by-step explanation:

The position of tower and the two persons has been shown in the figure below.

Let, h is the height of tower and the distance between tower and person B is x.

We can see in the figure that there are two triangles PAQ and PBQ and both are right angle triangles.

Now, In triangle PAQ, we can write

tan40⁰ = [tex]\frac{h}{x+6}[/tex]

Thus, 0.839 = [tex]\frac{h}{x+6}[/tex]

[tex]0.839x + 5.034 = h[/tex]

[tex]x = \frac{h- 5.034}{0.839}[/tex] Ā  Ā  (equation 1)

Again, in triangle PBQ, we can write

tan55⁰ = [tex]\frac{h}{x}[/tex]

Thus, 1.428 = [tex]\frac{h}{x}[/tex]

[tex]x = \frac{h}{1.428}[/tex] Ā  Ā  (equation 2)

Now, from equation 1 and equation 2, we can write

[tex]\frac{h-5.034}{0.839} = \frac{h}{1.428}[/tex]

[tex]1.428h - 7.188 = 0.839h[/tex]

[tex]0.589h=7.188[/tex]

[tex]h=12.2[/tex]

Thus the height of the tower will be 12.2 meters.

Ver imagen kamlesh678
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