Matthew claims y=square root of x is a function of x when x is greater than or equal to zero. Penny disagrees and offers this counterexample: when x=4, can be 2 or -2. Is Penny correct?
A.
Penny presented a valid counterexample, and she is correct that y= square root of x is NOT a function of x.
B.
Penny presented a flawed counterexample, but she is correct that y= square root of x is NOT a function of x.
C.
Penny is wrong; y=square root of x is a function of x.
D.
There is not enough information to answer this question.
A. Penny presented a valid counterexample, and she is correct that y= square root of x is NOT a function of x.
A. Penny presented a valid counterexample, and she is correct that y= square root of x is NOT a function of x.
The correct answer is A. Penny presented a valid counterexample, and she is correct that y = square root of x is NOT a function of x.
To determine if y = square root of x is a function of x, we need to check if each input value of x maps to a unique output value of y. In other words, for each value of x, there should be only one corresponding value of y.
Penny's counterexample is x = 4. When x = 4, the square root of x can be either 2 or -2. This means that there are two different values of y corresponding to the same input value of x, which violates the definition of a function.
Therefore, Penny is correct in asserting that y = square root of x is not a function of x.