I want to join 4 right triangle end to end around a central point, each 45 degrees rotated from the other, and I want to center them, by that central point, to the center of the "canvas". How can I do this? I want this to be precise.
For the centering... you might want to use snapping instead, to the rotation point of another object (e.g. a rectangle) centered in the middle of the page, if your triangle group is asymmetrical.
Beginners' Questions How to join triangles end to end?
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I want to join 4 right triangle end to end around a central point, each 45 degrees rotated from the other, and I want to center them, by that central point, to the center of the "canvas". How can I do this? I want this to be precise.
Draw your triangle.
Click on it twice (slowly) with the selection tool, so you get the rotation handles.
Activate snapping. Activate snapping to paths. Activate snapping to cusp corners. Activate snapping to rotation centers.
Grab the rotation center. Snap it to the tip of the triangle.
Duplicate the triangle (Ctrl+D)
Hold Ctrl.
Rotate the triangle (15° steps).
Repeat duplication + rotation two more times.
Group triangles.
Center group on page with Align + Distribtute dialog (from Objects menu).
For the centering... you might want to use snapping instead, to the rotation point of another object (e.g. a rectangle) centered in the middle of the page, if your triangle group is asymmetrical.