$\"\"$

The equation is $\"\"$ .

Since the standard form of linear function is $\"\"$ .

Solve the equation.

$\"\"$ (Original equation)

$\"\"$ (Subtract $\"\"$ from each side)

$\"\"$ (Apply additive inverse property: $\"\"$ )

$\"\"$ (Take out sqaure of each side)

$\"\"$ (Cancel square and root)

Square of the difference property: $\"\"$ .

Rewrite the equation is $\"\"$ .

The expression includes square of the variable.

So, $\"\"$ is $\"\"$ Thus, the function is not a linear function. $\"\"$

No.

The expression includes square of the variable.