Solve f(x) = x²: Finding the Function Point Where f(x) = 64

To solve this problem, we'll follow these steps:

• Step 1: Set up the equation based on the function and given value.
• Step 2: Solve the quadratic equation considering both positive and negative roots.

Now, let's work through each step:

Step 1: Set up the equation based on the given condition. We know that
$f(x) = x^2$ and we need $f(?) = 64$. So we equate:
$x^2 = 64$.

Step 2: Solve for $x$ using the square root rule, which tells us that if $x^2 = a$, then $x = \pm\sqrt{a}$.

Applying this to our equation:
$x = \pm\sqrt{64}$.
Calculate the square root: $\sqrt{64} = 8$.
Therefore, the solutions are $x = 8$ and $x = -8$.

Thus, we have $f(8) = 64$ and $f(-8) = 64$.

Among the given choices, $f(8)$ and $f(-8)$ is the correct choice.

Therefore, the missing value is $f(8)$ and $f(-8)$.