There are square tiles arranged in a pattern.
The pattern has rows that are 5 tiles wide and an unknown number of rows.
If you add one more tile, you can create a pattern that has rows that are 3 tiles wide,
with 3 more rows than the original pattern.
How many rows are in the original pattern?
The original pattern had rows and 5 columns.
. . There were tiles.
Add one tile.
The tiles can be arranged in rows and 3 columns.
. . There will be: . tiles.
There is our equation: .