Need on 5
is it function and explain why.

#5

It is not a function because the some x-values can have more than one possible y-value. The x-values can have the positive and negative y-value.

Step-by-step explanation:

The equation is the equation for a circle. When you graph a circle, it does not pass the vertical line test.

Example: if x is 6

6² + y² = 100

36 + y² = 100

y² = 100 - 36

y² = 64

y = ± √64   This is true because: (-8)² = 64 AND 8² = 64

y = -8 OR 8

By the way, for #4 it is not a function.

The points (13, 4) and (13, -4) mean that x will have more than one y value. The x-value 13 will have y-values 4 and -4.

x=half

step-by-step explanation: