public void Line_IsParallelTo() { Line line1 = new LineSegment(Point.MakePointWithInches(0,0), Point.MakePointWithInches(5,0)); Line line2 = new LineSegment(Point.MakePointWithInches(-3,-3), Point.MakePointWithInches(8,-3)); Line line3 = new LineSegment(Point.MakePointWithInches(1, 1), Point.MakePointWithInches(4, 1)); Line line4 = new LineSegment(Point.MakePointWithInches(0, 0), Point.MakePointWithInches(0, 5)); Line line5 = new LineSegment(Point.MakePointWithInches(-3, -3), Point.MakePointWithInches(-3, 8)); Line line6 = new LineSegment(Point.MakePointWithInches(1, 1), Point.MakePointWithInches(1,4)); line1.IsParallelTo(line2).Should().BeTrue(); line2.IsParallelTo(line3).Should().BeTrue(); line4.IsParallelTo(line5).Should().BeTrue(); line5.IsParallelTo(line6).Should().BeTrue(); line1.IsParallelTo(line4).Should().BeFalse(); line5.IsParallelTo(line3).Should().BeFalse(); }