Practise: Unique Rectangle
Look at the four marked corners: three show only pair 6/7; which fourth corner still has extra notes?
The prepared notes show three exact 6/7 pairs and one corner with extra options. Prove the rectangle first; this removes candidates and does not place a digit yet.
Example 1 of 4
Your turn first
Your turn first
Find three exact 6/7 pairs at rectangle corners. Which fourth corner has extra notes and therefore cannot keep the pair?
Remember
A Type 1 Unique Rectangle has three corners with the same exact pair and one corner with that pair plus extras. A unique puzzle cannot leave all four as the same pair, so remove the pair only from the extra corner.
Put it to use
Where you will meet it
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