Question

The Sine and Cosine Rules

Answer 1

Hello,
I am not doing that with sin, cos and pythagorean theorem.

DEFINITION: we call TAN x=sin x / cos x
This means that in a right triangle the tangent of an angle is the ration of opposed side by adjacent side.

11: tan 8°=12.5/d
==>d=12.5/tan 8°=12.5/0.14054...=88.942121...m≈88.9 (m)

12:
tan 28°=h/420
==>h=420*tan 28°=420*0.5317...=223.3179...≈223.3 (m)