Find a formula that expresses the fact that P(x, y) is a distance 9 from the origin.

x^2 + y^2 = 81

To find a formula that expresses the fact that a point P(x, y) is a distance of 9 from the origin, we can use the distance formula. The distance between two points (x1, y1) and (x2, y2) on a coordinate plane is given by:

d = √((x2 - x1)^2 + (y2 - y1)^2)

In this case, the first point is the origin, which has coordinates (0, 0), and the second point is P(x, y). So we can write the distance formula as:

9 = √((x - 0)^2 + (y - 0)^2)

Simplifying further:

81 = (x^2 + y^2)

Therefore, the formula that expresses the fact that P(x, y) is a distance 9 from the origin is x^2 + y^2 = 81.

To find a formula that expresses the fact that a point P(x, y) is a distance of 9 from the origin, we can use the distance formula.

The distance formula is given by:

d = √((x2 - x1)^2 + (y2 - y1)^2)

In this case, we want to find the distance from the origin to the point P(x, y). The origin is (0, 0), so we can substitute these values into the formula:

d = √((x - 0)^2 + (y - 0)^2)

Simplifying further:

d = √(x^2 + y^2)

Since we know that the distance is 9, we can equate it to the formula:

9 = √(x^2 + y^2)

To remove the square root, we square both sides:

81 = x^2 + y^2

Therefore, the formula that expresses the fact that P(x, y) is a distance 9 from the origin is x^2 + y^2 = 81.