You can rotate objects around a fixed point or flip them across an invisible axis that you specify. This axis can be horizontal, vertical, or angled.
How to rotate an object with the Mirror tool
    1. Select the object you want to mirror.
    2. Select the Mirror tool from the Tools panel.
    3. On the reference point locator, click a white square (1) to set a reference point (2) around which to rotate the object.
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        A crosshair symbol will be displayed in the defined position.
    4. Drag (rotate) the object to the desired position.
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    5. Optional: Specify a rotation angle.
        A positive angle means that the rotation is counterclockwise. A negative angle means that the rotation is clockwise.
    6. Optional: To use a constrain angle, hold down the Shift key while dragging.
        (The angle will be constrained to 15°, or the value you set in the Preferences.)
    7. Optional: To copy the object while rotating it, hold down the ALT key (Windows) or Option key(MacOS) while dragging.
How to rotate an object with the Selection tool
    1. Select the object you want to rotate.
    2. On the control panel of the Selection tool, click the Rotate button .
    3. On the reference point locator, click a white square (1) to set a reference point (2) around which to rotate the object.
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        A crosshair symbol will be displayed in the defined position.
    4. Place the cursor on an anchor point of the object frame and drag (rotate) the object to the desired position.
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    5. Optional: Specify a rotation angle.
        A positive angle means that the rotation is counterclockwise. A negative angle means that the rotation is clockwise.
    6. Optional: To use a constrain angle, hold down the Shift key while dragging.
        (The angle will be constrained to 15°, or the value you set in the Preferences.)
    7. Optional: To copy the object while rotating it, specify the number of copies.
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