関連ワード:  how to draw obtuse angle triangle    how to draw obtuse angle triangle bisector    how to draw obtuse angle triangle perpendicular bisector    how to draw obtuse angle triangle with compass    how to make obtuse angle triangle    how to construct obtuse angle triangle    how to draw altitude of obtuse angle triangle    how to draw medians of obtuse angle triangle    how to draw orthocentre of obtuse angle triangle    how to draw an obtuse angle isosceles triangle