Question 70821
 cable to the top of a tower makes an angle of 31deg with the level ground. At a point 100 yards closer to the tower the angle of elevation to the top of the tower is 57deg. Estimate the length of the cable.
:
If the angle to the tower is 57 we know the interior angle is 180 - 57 = 123
Let that angle be A and find the side opposite which is a
:
The third angle, which is opposite 100 yds is: 180 - 123 - 31 = 26 degrees
:
Use the law of sines:
{{{Sin(123)/a}}} = {{{Sin(26)/100}}}
:
{{{.83867/a}}} = {{{.43837/100}}}
:
Cross multiply:
.43837a = .83867*100
:
a = {{{83.867/.43837}}}
:
a = 191.3 yds