Question

Two trees, A and B are on the same side of a river. From a point C in the river the distance of thetrees A and B is 250m and 300m, respectively. If the angle C is 45, find the distance between the trees (use 2 =1.44).

Answer 1

AC = 250m
BC = 300m
angle C = 45 In triangle ABCUsing cosine formula a² = b² + c² - 2bc cosA
so, AB²= AC² + BC²- 2 AC x BC cos C
putting the values in equation 
= 62500 + 90000- 150000 x 1/√2
= 152500 - 106066.02
= 46433.98 

or AB = 215.5 m