Answer:
+ 24x + 16
Explanation:
If it is a square, all sides are equal. An area of a square would be side x side. You would multiply 3x + 4 and 3x + 4 together. I used the foil method (multiply first, then outside, inside, last) or (3x * 3x, 3x * 4, 4 * 3x, 4 * 4).