Answer:
The building is 61.5 m tall
Step-by-step explanation:
The image below is a diagram where all the given distances and angles are shown. We have additionally added some variables:
h = height of the building
a, b = internal angles of each triangle
x = base of each triangle
The angles a and b can be easily found by subtracting the given angles from 90° since they are complementary angles, thus:
a = 90° - 37° = 53°
b = 90° - 42° = 48°
Now we apply the tangent ratio on both triangles separately:
[tex]\displaystyle \tan a=\frac{\text{opposite leg}}{\text{adjacent leg}}[/tex]
[tex]\displaystyle \tan 53^\circ=\frac{150-x}{h}[/tex]
[tex]\displaystyle \tan 48^\circ=\frac{x}{h}[/tex]
From the last equation:
[tex]x=h.\tan 48^\circ[/tex]
Substituting into the first equation:
[tex]\displaystyle \tan 53^\circ=\frac{150-h.\tan 48^\circ}{h}[/tex]
Operating on the right side:
[tex]\displaystyle \tan 53^\circ=\frac{150}{h}-\tan 48^\circ[/tex]
Rearranging:
[tex]\displaystyle \tan 53^\circ+\tan 48^\circ=\frac{150}{h}[/tex]
Solving for h:
[tex]\displaystyle h=\frac{150}{\tan 53^\circ+\tan 48^\circ}[/tex]
Calculating:
h = 61.5 m
The building is 61.5 m tall
