Hey there! Could someone better at this game than me help me understand the hint I'm receiving? According to the hint, I can eliminate all 9s outside the rectangle, but I don't see why you can reach that conclusion. Any help?

This is the hint. Why can it state that 9 can only be on those squares? It's not obvious to me. Please save me…

Well for one, in that first row theres a pair of cells that can only have 8 or 9s, so the 9 has to go in that row.

If the left one turns out to be an 8, then the 689 below it becomes 69 (lol), and the other a 68. Since those were the only potential 9s in that row (just two of them), it forces the 9 in the left cell.

Basically the same thing happens any time there's a square made of two rows (or columns) with just two of a given number in each row (or column). That number has to be in one of those corners of the square - and not anywhere else in the row/column/block that contain those corners.

I see it!!! Thank you so much! I was so focused on seeing it by columns that I missed that detail!