Anchor point tool
Draw the top side of the triangle.
Select the anchor point tool.
Select the top corner (anchor point) of the triangle and drag it sideways.
Then, the handle pops out from the anchor point and changes to a curve (smooth point).
Click the point on the handle
Click a handle point with the Anchor Point tool to delete the handle and return directly.
When you click on a smooth point, the handle disappears and turns into an anchor point!
From round to square
If you click the anchor point of the curve with the anchor point tool, the handle will be deleted.
As you select smooth points with the Anchor Point tool, it becomes a rectangle!
If used properly, you will be able to handle round to square shapes freely!