When two vectors are acting at a point along different directions how do we determine magnitude and direction of the resultant?

The usual way to do this is to express each vector as the sum of two or three perpendicular vectors (two in a plane, three in 3D space). Then you can add the components of the two vectors, to get the new vector.For the case of two dimensions, on most scientific calculators there is a neat feature called rectangular-to-polar and polar-to-rectangular conversion, which can quickly convert a vector from polar (i.e., magnitude and angle) to rectangular (i.e., x-coordinate and y-coordinate), or vice versa.