When the vector sum of three co-planar forces,
,
and
, is parallel to
, we can conclude that
and
◦ must sum to zero.
◦ must be equal and opposite.
◦ must have equal and opposite components perpendicular to
.
◦ must have equal and opposite components parallel to
.
◦ must have equal and opposite components parallel and perpendicular to
.
must have equal and opposite components perpendicular to
.