A square yard (sq yd or yd²) is a unit of area commonly used in the United States and a few other countries. It is defined as the area of a square with sides that each measure one yard (3 feet) in length.
In terms of square feet, one square yard is equal to 9 square feet (1 yard * 1 yard = 3 feet * 3 feet = 9 square feet).
In terms of square meters, one square yard is approximately equal to 0.836127 square meters.
Square yards are often used in various applications, including real estate, landscaping, and construction, especially in the United States where the customary system of measurements is still prevalent.
A square kilometer (often abbreviated as km²) is a unit of area in the International System of Units (SI). It represents a square with sides that each measure 1 kilometer in length.
One square kilometer is equal to 1,000,000 square meters (m²) because there are 1,000 meters in a kilometer, and when you square that length, you get 1,000 * 1,000 = 1,000,000 square meters.
To visualize the size of a square kilometer, you can imagine a square plot of land, each side of which measures 1 kilometer (approximately 0.621 miles). It's a commonly used unit to measure land area, particularly in countries that use the metric system.