Posted by **jonathan** on Sunday, February 24, 2008 at 9:16pm.

Two ships, one sailing at 30 km/hr and the other at 45 km/hr, left port at the same time. Three hours later they were 120 km apart. If you had to find the angle between their courses an equation that could be used to solve this problem is:

- trig -
**Reiny**, Sunday, February 24, 2008 at 9:24pm
looks like a straightforward application of the cosine law.

120^2 = 90^2 + 135^2 - 2(90)(135)cosß

where ß is the angle between them

- trig -
**Damon**, Sunday, February 24, 2008 at 9:24pm
Ship A went 30 * 3 = 90 km

Ship B went 45 * 3 = 135 km

So we have a triangle with legs of 90 and 135 and an opposite side of 120

Use the law of cosines

120^2 = 90^2 + 135^2 - 2*90*135 cos T

solve for T

## Answer this Question

## Related Questions

- Pre Calc! - Two ships, one sailing at 30 km/hr and the other at 45 km/hr, left ...
- Math - Two ships left the same port at the same time. One travelled at 16kn/h on...
- Calculus - Two ships are leaving port at the same time. The first ship is ...
- trig - Help! Ships A and B leave port at the same time and sail on straight ...
- calculus - We know this is a piecewise function and we solved the first part, ...
- trig - two ships p and q left a port at the same time. q sailed on a bearing of...
- Maths- calculus - Two ships leave different ports A and B 100 miles apart at ...
- Pre-Calculus-Trig - Two trains depart simultaneously from the same station. The ...
- math - At 5 p.m two ships started sailing toward each other from ports which ...
- Algebra - At 3PM, two ships started sailing toward each other from ports which ...

More Related Questions