Which is the correct calculation of the y-coordinate of point
A?

Answer:
y = [tex]\sqrt{3}[/tex]
Step-by-step explanation:
The given circle has a radius of 2 thus OA = 2 , hypotenuse of right triangle
Using Pythagoras' identity in the right triangle formed to find y
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
1² + y² = 2²
1 + y² = 4 ( subtract 1 from both sides )
y² = 3 ( take the square root of both sides )
y = [tex]\sqrt{3}[/tex]
Thus A = (1, [tex]\sqrt{3}[/tex] )