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1. Select the first tangent object, close to the point of tangency.
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2. Select the second tangent object, close to the point of tangency.
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3. Size the circle with the mouse; the arc will be cut from this circle. Or enter the radius, diameter, or circumference in the Inspector Bar.
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4. Move the cursor to either side of the arc to determine the arc segment that will remain.
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Tangent Arc of Fixed Size

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