Answer: (1, √15) and (1, -√15)
Step-by-step explanation:
A circle centered at the point (a, b) of radius R can be written as:
(x - a)^2 + (y - b)^2 = R^2
In this case we have:
"A circle is centered at the origin (0,0) and has a radius of 4 units"
Then the equation for this circle is:
x^2 + y^2 = 4^2 = 16.
Now, we want to find the points where x = 1, then we can replace that value and solve the equation for y.
1^2 + y^2 = 16
1 + y^2 = 16
y^2 = 16 - 1 = 15
y = +-√15
Then the two points that have the x-coordinate equal to 1 are:
(1, √15) and (1, -√15)