# Thread: Obtuse Triangles - Help with drawing!

1. ## Obtuse Triangles - Help with drawing!

Hi, I received this question today. I need help with the placement of the 120 degree angle and 20 degree angle. The wording is confusing. Any help is appreciated.

Thanks!

A surveyor is measuring the length of a lake. He takes angle
measurements from two positions, A and B, that are 136 m apart
and on the same side of the lake. From B, the measure of the angle
between the sight lines to the ends of the lake is 130°, and the
measure of the angle between the sight lines to A and one end of
the lake is 120°. From A, the measure of the angle between the
sight lines to the ends of the lake is 65°, and the measure of the
angle between the sight lines to B and the same end of the lake is
20°. Calculate the length of the lake, to the nearest metre.

2. ## Re: Obtuse Triangles - Help with drawing!

Originally Posted by mmonkman
Hi, I received this question today. I need help with the placement of the 120 degree angle and 20 degree angle. The wording is confusing. Any help is appreciated.

Thanks!

A surveyor is measuring the length of a lake. He takes angle
measurements from two positions, A and B, that are 136 m apart
and on the same side of the lake. From B, the measure of the angle
between the sight lines to the ends of the lake is 130°, and the
measure of the angle between the sight lines to A and one end of
the lake is 120°. From A, the measure of the angle between the
sight lines to the ends of the lake is 65°, and the measure of the
angle between the sight lines to B and the same end of the lake is
20°. Calculate the length of the lake, to the nearest metre.