For this we need to use sinus law because there is no right angle in the observed triangle to solve it in some easier way.
\(\frac{a}{sin( \alpha )} = \frac{b}{sin( \beta )}\)
where a is height of the water tower, b is length from point of view till bottom of the tower, \(\alpha\) is the angle from point of view and \(\beta\) is angle opposite from b.
We use this law to calculate beta angle.
\(sin( \beta ) = \frac{b}{a} *sin( \alpha )\)
\(sin( \beta ) = 0.742\)
\(\beta = 47,924\)
Now we observe different angle. Bottom of the hill-top of the tower-point of view. We calculate angle at point of view (notice how it is different than previous one).
180-90-47.924 = 42.076
At last, the hill inclination is:
42.076 - 8 = 34.076 = 34.1
