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This fits the four vertices of the rectangle we have created to the size of the Graphics Window.
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Repeat this process to create edges between vertices 2 & 3, vertices 3 & 4, and vertices 4 & 1.
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Click Close. Then click Apply in the Create Face From Wireframe window to create the face. The edges and vertices will become blue, indicating that they now form a face.
(click picture for larger image)
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