We have been given diagram of a triangle. We are asked to write an expression that represents the distance between Seattle and San Francisco.
We will use law of cosines to solve our given problem.
, where a, b and c are sides corresponding to angle A, B and C.
Let the distance between Seattle and San Francisco be 'c' and
.
Using law of sines, we can set an equation as:
![c^2=1737^2+1858^2-2(1737)(1858)\text{cos}(21.4)](https://img.qammunity.org/2021/formulas/mathematics/high-school/jfnmud8opdkgez510lxqyoth6d9t83d6vg.png)
Upon taking square root in both sides, we will get:
![c=\sqrt{1737^2+1858^2-2(1737)(1858)\text{cos}(21.4)}](https://img.qammunity.org/2021/formulas/mathematics/high-school/yz0uco83bt64llx5r17vf50dbvxi8u2sq5.png)
Therefore, we can use the expression
can be used to find distance between Seattle, WA, and San Francisco, CA.