     Sudoku Solution Path   Copyright © Kevin Stone R4C7 can only be <7> R5C4 can only be <2> R5C2 can only be <9> R3C4 can only be <1> R4C5 can only be <3> R7C4 can only be <6> R4C3 can only be <2> R6C5 can only be <4> R5C3 can only be <1> R6C3 can only be <3> R6C7 can only be <9> R1C2 is the only square in row 1 that can be <2> R3C5 is the only square in row 3 that can be <2> R3C9 is the only square in row 3 that can be <9> R7C7 is the only square in row 7 that can be <2> R7C3 is the only square in row 7 that can be <9> R9C7 is the only square in row 9 that can be <1> Intersection of row 9 with block 7. The value <6> only appears in one or more of squares R9C1, R9C2 and R9C3 of row 9. These squares are the ones that intersect with block 7. Thus, the other (non-intersecting) squares of block 7 cannot contain this value.    R8C3 - removing <6> from <4567> leaving <457> Intersection of column 7 with block 3. The value <3> only appears in one or more of squares R1C7, R2C7 and R3C7 of column 7. These squares are the ones that intersect with block 3. Thus, the other (non-intersecting) squares of block 3 cannot contain this value.    R3C8 - removing <3> from <34578> leaving <4578> Intersection of column 9 with block 9. The value <7> only appears in one or more of squares R7C9, R8C9 and R9C9 of column 9. These squares are the ones that intersect with block 9. Thus, the other (non-intersecting) squares of block 9 cannot contain this value.    R7C8 - removing <7> from <3457> leaving <345>    R9C8 - removing <7> from <37> leaving <3> R9C2 can only be <6> R9C3 can only be <7> R1C8 is the only square in row 1 that can be <7> R3C1 is the only square in row 3 that can be <7> Squares R1C3 and R1C7 in row 1 and R8C3 and R8C7 in row 8 form a Simple X-Wing pattern on possibility <5>. All other instances of this possibility in columns 3 and 7 can be removed.    R2C3 - removing <5> from <4568> leaving <468>    R2C7 - removing <5> from <34568> leaving <3468>    R3C3 - removing <5> from <4568> leaving <468>    R3C7 - removing <5> from <34568> leaving <3468> R2C5 is the only square in row 2 that can be <5> R5C5 can only be <7> R3C6 can only be <8> R7C6 can only be <7> R5C6 can only be <5> R8C5 can only be <1> R7C9 can only be <4> R7C8 can only be <5> R2C9 can only be <6> R8C1 can only be <4> R7C5 can only be <8> R8C9 can only be <7> R7C2 can only be <3> R3C8 can only be <4> R8C7 can only be <6> R8C3 can only be <5> R2C1 can only be <3> R1C3 can only be <8> R1C7 can only be <5> R2C3 can only be <4> R7C1 can only be <1> R3C2 can only be <5> R2C7 can only be <8> R3C3 can only be <6> R5C7 can only be <4> R3C7 can only be <3> R5C8 can only be <8> [Puzzle Code = Sudoku-20190822-VeryHard-298365]    