Yes, let's go through the steps to continue solving the problem based on where you left off.

In the final part of your work, you reached the expression:

$A - \sqrt{(A+G)(A-H)} = \frac{a}{b}$

To proceed from here, we should ideally simplify or solve this equation depending on what the problem requires. Here’s a step-by-step approach:

1. Square Both Sides: To remove the square root, you can square both sides of the equation. This would result in: $(A - \sqrt{(A+G)(A-H)})^2 = \left(\frac{a}{b}\right)^2$

2. Expand the Left Side: Expanding the squared term on the left-hand side gives: $A^2 - 2A \cdot \sqrt{(A+G)(A-H)} + (A+G)(A-H) = \frac{a^2}{b^2}$

3. Isolate the Square Root Term: Move terms to isolate the square root term on one side: $-2A \cdot \sqrt{(A+G)(A-H)} = \frac{a^2}{b^2} - A^2 - (A+G)(A-H)$

4. Square Both Sides Again (if needed): At this point, you might need to square both sides again to fully eliminate the square root, which will result in a polynomial equation.

5. Solve for $A$ in Terms of $a$ and $b$: Once you have eliminated the square root, you’ll have an equation involving $A$, $a$, and $b$. Solve this for $A$ or any other variable that the question is asking you to isolate.

Would you like further help on any of these steps, or would you like me to work through it fully?

Here are some related questions that could deepen understanding:

1. Why do we need to square both sides to eliminate the square root?
2. What are the potential pitfalls of squaring both sides of an equation?
3. How can we verify that our solution is valid for all values of $a$ and $b$?
4. Could this equation have multiple solutions, and if so, how can we identify them?
5. What strategies could simplify dealing with square roots in similar problems?

Tip: Always check your final answer by substituting it back into the original equation to ensure it satisfies all conditions given.