I'm not quite sure what you mean but it is a measure of area.
621 square feet
The dimensions would be 40 feet by 40 feet.
Find the square root. For example, 25 sq. ft can be visualized as a 5 foot square, since 5 is the square root of 25. Often, you can factor the square foot dimension to help you visualize the area. For example, 32 square feet : 8 x 4 = 32 A sheet of plywood 8 feet long and 4 feet wide covers an area of 32 square feet.
Each side is 8 feet long !
7 The dimension you provide is not a squared dimension but a linear dimension. There are no squared dimensions in a linear dimension. There are 7 linear yards in 21 linear feet, but no squared yards.
Multiply the two dimension to get area. The answer would be 2,736 square feet.
You calculate the square feet of the room/ area. A square feet is still a square feet, no matter on the dimension of the tile
Answer: 1 acre = 43,560 ft²
You don't. Yard is distance (one dimension) square feet is area (two dimensions).
The area is found by multiplying the two dimension. This would be 1,600 square feet.
You need one more piece of information. One other dimension (if a rectangular area), in feet, of the area you are using/measuring. Take "the other dimension in feet" and divide it by 9. Assuming your other dimension is 12 feet, 12/9 = 1.333333, therefore in your case do this 4840/1.333333 = 3630 lineal feet. Warning, this only works on rectangular areas.
Because the units of area have dimension 2 - as in square centimetres or square feet.