public void ThreePointsAreFlat_ReturnTrue() { Point p1 = new Point() { 0.0, 0.0, 0.0 }; Point p2 = new Point() { 10.0, 0.0, 0.0 }; Point p3 = new Point() { 5.0, 5.0, 0.0 }; Point p4 = new Point() { -5.0, -15.0, 0.0 }; List <Point> points = new List <Point>() { p1, p2, p3, p4 }; Trig.ArePointsCoplanar(points).Should().BeTrue(); }