Evaluate 3x*3x

$3 x \cdot 3 x$

Rewrite using the commutative property of multiplication.

$3 \cdot 3 x \cdot x$

Multiply $x$ by $x$ by adding the exponents.

Move $x$ .

$3 \cdot 3 (x \cdot x)$

Multiply $x$ by $x$ .

$3 \cdot 3 x^{2}$

Multiply $3$ by $3$ .

$9 x^{2}$