Simply put; polar coordinates are used to show how far away a point is and at what angle it is so, for example, you have the length of a diagonal line (r)and the angle formed `` between the x-axis and the point
(r;`theta` ).You would convert using the cos or sin function depending on what you need to find.
as opposed to what you are used to with x and y coordinates which measure how far up (on this graph 2) and how far across(4) rendering coordinates of (4;2).
Polar coordinates are used when solving for direction and length from a certain point. Some otherwise complicated calculations for curves are simplified using polar coordinates. Thus, they are used to show
how far away a point is and at what angle it is
In Cartesian or xy-plane points are written as (x,y) where as in polar coordinate system points are written as (r,`theta` ).
A relation between these two system is defined as
`y=r sin(theta)` `theta=tan^-1(y/x)` and `r=sqrt(x^2+y^2)` say triangle OBC , angle B=90