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Trig Tan Math problem

Ive tried to work these problems but am unsure of how exactly to get the correct answer.

 a man jumps out of a plane at 4250 feet directly over his target and falls 82 degress to the ground. How far did he miss his target?

 

A tree cast a shadow of 12 feet and the distance from the end of the shadow to the top of the tree is 13 feet. How tall is the tree?

What is the answer and how did you work this problem out step by step.

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3 Answers

tan 82° = x / 4250

(tan 82°) * 4250 = x

x ≈ 30240.32 ft. ( I don't know if I interpreted the problem right.)

 

Second problem:

This is a right triangle problem.

In this case the base of triangle is 12 feet and the hypotenuse is 13 feet.

use pythagorean theorem:  a2 + b2 = c2

122 + b2 = 132

144 + b2 = 169

b2 = 169 - 144

b2 = 25

b = 5 feet.

so, the tree is 5 feet tall.

 

 

 

 

                  B
                 /|      
               /  |      
             /    |      ↑    
           /      |   4250 ft
         /        |      ↓
    A / 820    | C                 

  BC / AC = tan 820 ---> AC = BC / tan 820
B                                  AC ≈ 4250 ÷ 7.11537 = 597.3 ft
|\         
|   \       
|      \    13 ft
|          \   
|    12 ft   \  A  
C

 a2 + b2 = c2 ---> a2 = 132 - 122 = 25 ---> a = 5 ft
OR
cos A = AB / AC
cos A = 12 / 13 = 0.923077
measure of angel A = 22.620 
sin 22.620 = BC / AB ---> BC = AB * sin 22.620 ---> BC = 13 * 0.3846 = 5 ft

You have two problems here.  For the first one, a very good explanation can be found here on  how to proceed

http://www.mathsisfun.com/algebra/trig-finding-side-right-triangle.html

You have the angle (82 degrees) and the adjacent side (4250 feet) but need the opposite side's measurement, so you are working with the tangent.

The second is classic Pythagorus: tree height is A  (? feet), shadow cast  (12 feet) is B, shadow tip to tree top is C (13 feet or the hypotenuse{H}).

Draw the picture, it will help makes things clearer.

So, A-squared plus B-squared equals C-squared:

A2 + B2 = C2

A2 + 122 = 132

A2 + 144 = 169

Move B to the right side of the equation

A2 = 169 - 144

Subtract B from C

A2 = 25

Take the square root of both sides of the equation

A = 5

The tree is 5 feet tall.