Answer:
The angle of elevation is approximately [tex]64.8^o[/tex]
Step-by-step explanation:
Notice that the two pieces of information given: "400 ft away from a building", and building that is "850 ft tall", can be regarded as the two legs of a right angle triangle (see attached image).
Then the angle [tex]\theta[/tex] that we are trying to find (the angle of elevation) can be found by using the arc-tangent function:
[tex]tan(\theta)=\frac{850}{400} \\tan(\theta)=\frac{17}{8}\\\theta =arctan(\frac{17}{8})\\\theta = 64.8 ^o[/tex]
