1. The problem asks for the area of a square with side length $4x + 3$. 2. The formula for the area of a square is: $$\text{Area} = (\text{side length})^2$$ 3. Substitute the side length $4x + 3$ into the formula: $$\text{Area} = (4x + 3)^2$$ 4. Expand the square using the formula $(a + b)^2 = a^2 + 2ab + b^2$: $$ (4x + 3)^2 = (4x)^2 + 2 \times 4x \times 3 + 3^2 $$ 5. Calculate each term: $$ (4x)^2 = 16x^2 $$ $$ 2 \times 4x \times 3 = 24x $$ $$ 3^2 = 9 $$ 6. Combine all terms: $$ \text{Area} = 16x^2 + 24x + 9 $$ This is the simplest expanded expression for the area of the square.