Question

A surveyor measures the lengths of the sides of a triangular plot of land. What is the measure of the angle of the triangular plot at which the surveyor stands? Approximate to the nearest degree.

cos–1(0.75) = 41°
cos–1(0.125) = 83°
cos–1(0.15) = 89°

Answer 1

the second one is correct

Answer 2

Answer: Second option is correct.

Explanation:

Since we have given that

a = 300 m

b = 250 m

c = 200 m

We need to find the measure of angle i.e. A

As we know the "Law of Cosine rules ":

`\cos A=(b^2+c^2-a^c)/(2bc)\\\\\cos A=(250^2+200^2-300^2)/(2* 250* 200)\\\\\cos A=(12500)/(100000)\\\\\cos A=0.125\\\\A=\cos^(-1)(0.125)\\\\A=82.81^\circ\\\\A\approx 83^\circ`

Hence, Second option is correct.