Three forces of magnitude 6N,6N,√72N act at a corner of a cube along three sides .resultant of the force is a)12N along on b)18N along oa c)18N along of d)12N along oe

Answer 1

the magnitude z is

z^2 = 6^2+6^2+72 = 144
z = 12

Not sure where N and E are ...