How to align the corner of a plane with the cnr of a body

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1

I have a body, and a sketch, and need to align the corner of the sketch with the corner of the body (it will be a leg, with precisely positioned holes. Once positioned, I can extrude the leg.

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I can extrude the leg, but how to align the corners of the two bodies?

image

2

I would extrude the leg first then use either the Translate tool or the Align tool.