How can you prove that 9 square feet equals 1 square yard?

Answer 1

1 square yard is the area of a square of side 1 yard, since 1 yard x 1 yard = 1 square yard.

1 yard is 3 feet in length, so each side of a square with 1 yard in length will be 3 feet in length.

The area of this square is 3 feet x 3 feet = 9 square feet.

But this square also has an area of 1 square yard, and so these areas must be the same.

Thus 1 square yard = 9 square feet.

Symbolically:

1 yd = 3 ft

1 sq yd = 1 yd x 1 yd

= 3 ft x 3 ft

= 9 sq ft.