Question

the dimensions of the base of box 1 are $x$ by $3x$.
the base area of box 1 is:
$3x$
$3x^2$
$3x^3$
$4x$
done

Explanation:

Step1: Recall rectangle area formula

Area = length × width

Step2: Substitute given dimensions

Area = $x \times 3x$

Step3: Simplify the expression

Area = $3x^{1+1} = 3x^2$

Answer:

$\boldsymbol{3x^2}$ (the second option)