Question

Distance across river (ab) has a distance bc=235 feet. Angle b is 101 degrees and angle c is 30 degrees. What's the distance across the river?

Answer 1

Step 1:

Distance across river has a distance .

Angles are .

Find the distance across the river .

Draw the diagram.

Observe the diagram,

Here, is the distance across the river.

Sine rule is .

Substitute and in the sine rule.

Find the angle .

Substitute in .

Angle .

Step 2:

Find length of .

Substitute in the sine rule.

Consider,

The distance across the river is .

Solution :

The distance across the river is .