1. override
Constraint operator >=(EquationMember value)

Creates a Constraint by using this member as the left hand side expression and the argument as the right hand side Expression of a Constraint with a Relation.greaterThanOrEqualTo relationship between the two.

For example: right - left >= cm(200.0) would read, "the width of the object is at least 200."

Source 

@override
Constraint operator >=(EquationMember value) {
  return _createConstraint(value, Relation.greaterThanOrEqualTo);
}