The right angle pattern can help you find numbers when there is only one of the same number in both a row and a column. It is a mix between the diagonal and the corner pattern. When a number fits into the right angle pattern it makes a corner pattern.
The right angle pattern is seen when three cells that are at ‘right angles’ with each other have numbers. Here is an example of several right angle patterns.
Look at boxes 2, 4, 6 and 8. They all have three cells populated and each one of them have a right angle pattern.
When a right angle pattern exists it gives us the opportunity to find a number by looking at the row and the column that aren’t a part of the pattern. Look at box 2 in figure 2 below. Row 1 and column 4 aren’t a part of the right angle pattern in that box. That means we can look at that row and column for a single number that is a) in both the row and column that is b) not already in box 2.
There is an 8 in row 1 and column 4. Box 2 doesn’t have an 8, so 8 is the only number that can fit in the ‘pocket’ of the right angle pattern. The number in r2c5 is therefore 8.
Now let’s look at box 4. Follow the same logic and you will see that the ‘pocket’ of the right angle pattern in box 4 holds a 2. Box 6 has a 1 in the pocket of its pattern and box 8 has a 6. See figure 3 below and convince yourself that each of the green numbers belong in their respective cells.
Finding right angle patterns and filling in their 'pocket' will benefit you with both a number and a corner pattern. This will help find other numbers because a corner pattern can also help you find numbers.
This video talks about the right angle pattern and shows examples of it.
The right angle pattern can be found in any skill level puzzle.
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