Answer:
Picture 1 has 5 green squares. It is one square with a square coming out from each corner. Picture 2 adds an additional square extending out from each corner square, making a total of 9 squares. This pattern continues, adding 4 green squares total each time. This means Picture 3 has 13 squares, Picture 4 has 17 squares, and Picture 5 will have 21 green squares.
Step-by-step explanation:
Picture one has 5 green squares. It is one square with a square coming out from each corner. Picture 2 adds an additional square extending out from each corner square, making a total of 9 squares. This pattern continues, adding 4 squares total each time. This means Picture 3 has 13 squares, Picture 4 has 17 squares, and Picture 5 will have 21 squares.