Hello, Joker37!

Did you make a sketch?

To calculate the height of a crane which is on top of a building,

Denis measures the angle of elevation to the bottom and top of the crane.

These were 62° and 68° respectively.

If the building is 42 m high find, to 2 decimal places:

a) how far Denis is from the building

b) the height of the crane. Code:

A o
|\
| \
y | \
| \
| \
B o \
| * \
| * \
42 | *6°\
| * \
| 62° *\
C o - - - - - o D
x

The crane is $\displaystyle AB = y.$

The building is $\displaystyle BC = 42.$

Denis is at $\displaystyle D\!:\;CD = x$

$\displaystyle \angle BDC = 62^o,\;\angle ADC = 68^o$

(a) In right triangle $\displaystyle BCD\!:\;\;\tan 62^o \:=\:\frac{42}{x} \quad\Rightarrow\quad x \:=\:\frac{42}{\tan62^o} \;\approx\;22.33$ ft.

(b) In right triangle $\displaystyle ACD\!:\;\;\tan68^o \:=\:\frac{y+42}{x} \quad\Rightarrow\quad y \:=\:x\tan68^o - 42 \;\approx\;13.27$ ft.

Edit: Too slow again . . . *sigh*

.