We are asked to subtract:

$(28a^2 - 10) - (5a^2 - 2b + 6)$

Step 1: Distribute the negative sign

When subtracting, we distribute the negative sign across the terms in the second expression:

$(28a^2 - 10) - (5a^2 - 2b + 6) = 28a^2 - 10 - 5a^2 + 2b - 6$

Step 2: Combine like terms

Now, let's simplify the expression by combining like terms:

$28a^2 - 5a^2 = 23a^2$

$-10 - 6 = -16$

So the final expression becomes:

$23a^2 + 2b - 16$

Answer:

This corresponds to the third option in the image:

$\boxed{23a^2 + 2b - 16}$

Would you like more details or have any questions? Here are five related questions to extend this topic:

1. What would the result be if the operation was addition instead of subtraction?
2. How do you distribute a negative sign when subtracting polynomials?
3. What are some key steps to combine like terms in an algebraic expression?
4. Can we represent this subtraction using matrices, and how would that work?
5. How does this type of operation apply in solving real-world problems?

Tip: Always check for like terms (terms with the same variables and powers) to simplify expressions correctly.