Step-by-Step Solution

for Thursday 19th December Diabolical

For row 8, number 9 is only possible in cell (6,8)

Single Position

For row 6, number 7 is only possible in cell (2,6)

Single Position

For column 1, Number 7 is only possible in cell (1,7)

Single Position

For row 2, number 4 is only possible in cell (4,2)

Single Position

For row 7, number 4 is only possible in cell (3,7)

Single Position

For row 5, number 4 is only possible in cell (1,5)

Single Position

For row 4, number 4 is only possible in cell (8,4)

Single Position

For row 4, number 5 is only possible in cell (5,4)

Single Position

For column 5, Number 9 is only possible in cell (5,6)

Single Position

For row 9, number 5 is only possible in cell (9,9)

Single Position

For row 2, number 5 is only possible in cell (2,2)

Single Position

For row 2, number 9 is only possible in cell (8,2)

Single Position

For row 1, number 9 is only possible in cell (2,1)

Single Position

For row 2, number 8 is only possible in cell (9,2)

Single Position

For row 3, number 5 is only possible in cell (7,3)

Single Position

For row 1, number 5 is only possible in cell (4,1)

Single Position

For row 1, number 8 is only possible in cell (5,1)

Single Position

For column 4, Number 7 is only possible in cell (4,9)

Single Position

For row 4, number 3 is only possible in cell (7,4)

Single Position

Number 1 is the only value possible in cell (7,1).

Single Candidate

For row 4, number 9 is only possible in cell (3,4)

Single Position

For row 5, number 9 is only possible in cell (7,5)

Single Position

For row 5, number 8 is only possible in cell (3,5)

Single Position

For row 5, number 1 is only possible in cell (9,5)

Single Position

For row 6, number 1 is only possible in cell (3,6)

Single Position

For box 1, Number 1 is only possible in cell (1,2)

Single Position

Number 3 is the only value possible in cell (6,2).

Single Candidate

For row 8, number 1 is only possible in cell (2,8)

Single Position

For row 7, number 3 is only possible in cell (5,7)

Single Position

X-Wing in columns for 2.

X-Wings

For box 9, candidates for 2 are all in row 8, so you can remove candidates from other blocks.

Candidate Lines

Either candidate for cell (3,9) forces 8 into cell (4,8).

Forcing Chains

Either candidate for cell (3,9) forces 8 into cell (2,9).

Forcing Chains

For row 7, number 8 is only possible in cell (7,7)

Single Position

Number 6 is the only value possible in cell (7,6).

Single Candidate

Number 2 is the only value possible in cell (9,6).

Single Candidate

Number 8 is the only value possible in cell (8,6).

Single Candidate

For row 8, number 2 is only possible in cell (8,8)

Single Position

Either candidate for cell (1,1) forces 6 into cell (9,3).

Forcing Chains

Number 3 is the only value possible in cell (9,8).

Single Candidate

Number 6 is the only value possible in cell (1,8).

Single Candidate

Number 2 is the only value possible in cell (1,4).

Single Candidate

Number 3 is the only value possible in cell (1,1).

Single Candidate

Number 7 is the only value possible in cell (8,1).

Single Candidate

Number 2 is the only value possible in cell (6,1).

Single Candidate

Number 2 is the only value possible in cell (3,3).

Single Candidate

Number 1 is the only value possible in cell (5,3).

Single Candidate

Number 7 is the only value possible in cell (6,3).

Single Candidate

Number 3 is the only value possible in cell (8,3).

Single Candidate

Number 6 is the only value possible in cell (2,4).

Single Candidate

Number 6 is the only value possible in cell (6,5).

Single Candidate

Number 2 is the only value possible in cell (4,5).

Single Candidate

Number 2 is the only value possible in cell (2,7).

Single Candidate

Number 6 is the only value possible in cell (4,7).

Single Candidate

Number 3 is the only value possible in cell (3,9).

Single Candidate

Number 2 is the only value possible in cell (5,9).

Single Candidate

Number 1 is the only value possible in cell (6,9).

Single Candidate

Number 6 is the only value possible in cell (8,9).

Single Candidate