The expression you've written is $(7 \times 4)^2$. To solve this:

1. First, multiply $7 \times 4$: $7 \times 4 = 28$

2. Now, square the result: $28^2 = 28 \times 28 = 784$

So, $(7 \times 4)^2 = 784$.

Would you like more details or have any questions? Here are some related questions to consider:

1. What is the difference between squaring and cubing a number?
2. How do you calculate higher powers, such as $28^3$?
3. What are the properties of exponents when multiplying or dividing powers?
4. How can you simplify an expression involving multiple exponents?
5. What is the significance of order of operations in solving expressions like $(7 \times 4)^2$?

Tip: Always remember the order of operations (PEMDAS: Parentheses, Exponents, Multiplication/Division, Addition/Subtraction) when solving math problems.