Find a formula that expresses the fact that P(x, y) is a distance 2 away from the origin.?

Question

pre cal prob

Answer 1

x ² + y ² = 2 ²
x ² + y ² = 4
(the equation of a circle centre O , radius 2)

Answer 2

Remember the distance formula, based on the pythagorean theorem?

If you have a horizontal distance x and a vertical distance y, then the hypotenuse will be x² + y²

So your formula is x² + y² = 2²
or
x² + y² = 4

Or solving in terms of y:

y² = 4 - x²
y = sqrt(4 - x²)

Answer 3

pythagoras' theorem
c^2 = a^2 + b^2

4 = x^2 + y^2

x^2 + y^2 - 4 = 0

y^2 = 4 - x^2

y = sqrt(4 - x^2)