To determine if the equation x^2 + y^2 = 9 is a function, we can graph it on a coordinate plane and see if it passes the vertical line test.
The equation can be rewritten as y = ±√(9 - x^2).
By graphing the positive square root of this equation and the negative square root of this equation, we can see that it forms a circle with a radius of 3 centered at the origin (0, 0).
A circle is not a function because it does not pass the vertical line test. For certain x-values, there are two corresponding y-values on the circle. Therefore, x^2 + y^2 = 9 is not a function.
Determine if x^2+y^2=9
is a function by graphing.
1 answer
1 answer