At a certain time of the day, a tree that is x meters tall casts a shadow that is x-49 meters long. If the distance from the top of the tree to the end of the shadow is x+1 meters, what is the height , x of the tree ?

Respuesta :

The height of the tree is 60 meters.

Explanation:

Let the height of the tree be x. The tree casts a shadow of [tex]x-49[/tex] meters and the distance from the top of the tree to the end of the shadow is [tex]x+1[/tex] meters.

The sides of the triangle are attached in the image below:

Using pythagoras theorem,

[tex]x^{2}+(x-49)^{2}=(x+1)^{2}[/tex]

Expanding, we get,

[tex]2 x^{2}-98 x+2401=x^{2}+2 x+1[/tex]

[tex]2 x^{2}-98 x+2400=x^{2}+2 x[/tex]

[tex]2 x^{2}-100 x+2400=x^{2}[/tex]

[tex]x^{2}-100 x+2400=0[/tex]

Solving the equation using the quadratic formula [tex]x=\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a}[/tex], we get,

[tex]x=\frac{-(-100)\pm\sqrt{(-100)^{2}-4 \cdot 1 \cdot 2400}}{2 \cdot 1}[/tex]

Simplifying, we have,

[tex]x=\frac{100\pm\sqrt{10000-9600}}{2}[/tex]

[tex]x=\frac{100\pm\sqrt{400}}{2}[/tex]

[tex]x=\frac{100\pm{20}}{2}[/tex]

Thus,

[tex]x=\frac{100+20}{2} \\x=\frac{120}{2} \\x=60[/tex]  and  [tex]x=\frac{100-20}{2} \\x=\frac{80}{2} \\x=40[/tex]

where the value [tex]x=40[/tex] is not possible because substituting the value [tex]x=40[/tex] in [tex]x-49[/tex] results in negative solution. Which is not possible.

Hence, the value of x is 60.

Thus, The height of the tree is 60 meters.

Ver imagen vijayalalitha