Answer:
600 square inches
Explanation:
Let each square be x by x inches.
When you place 6 squares side by side, the total length is 6x.
The width is x.
perimeter = 2(length + width)
perimeter = 2(6x + x)
perimeter = 14x
14x = 140 inches
x = 10 inches
length of the rectangle: 6x = 6 × 10 inches = 60 inches
width of the rectangle: x = 10 inches
area = length × width
area = 60 inches × 10 inches
area = 600 square inches