state whether the relation is a function a) y= -2√x-2+4

Question

2.state whether the relation is a function

a) y= -2√x-2+4

b) y=3 (x-2)² -4

Answer 1

a is not a function, it's a leftward opening parabola

b is a function, it's an upward opening parabola

use the vertical line test, if there's more than one y value for a given x value, it's not a function. If a vertical line cuts the graph in more than one place, it's not a function.