My patio is tiled with square tiles, all the same size. All the tiles are gray, except the tiles along the two diagonals, which are all yellow. (The corners are yellow, the center is yellow, and all the tiles along the diagonal in between are yellow.) If there are 89 yellow tiles, how many gray tiles are there?
thanks to whoever helps!
The amount of diagonal tiles can be written as 2x-1 where x is the side length of the square. That means that 2x-1 = 89; x= 45. The area of the square is 45 * 45= 2025. 2025-89 yellow tiles= 1936 gray tiles.
Also, MooMooooMooM answered here first, but this is an explanation as well.