Equation of a parabola with vertex at (2, -1) is
y = a(x - 2)^2 - 1
Using the given point: -3 = a(4 - 2)^2 - 1
-2 = a(2)^2
4a = -2
a = -1/2
Therefore, required equation is
y = -1/2(x - 2)^2 - 1
y = -1/2(x^2 - 4x + 4) - 1
y = -1/2x^2 + 2x - 2 - 1
y = -1/2x^2 + 2x - 3
EQUATION OF A CIRCLE: (x-h)² + (y-k)² =r²
= (x+1)² + (y-4)² =3
Answer: Yes
If I remember correctly, I believe these ordered pairs indicate a function, as there is exactly 1 output for every input (i.e., (output, input)). If there were 2 inputs of the same number, that'd make this relation not a function.
