The problem describes a rectangle where the length is twice the width, and its area is 94 square units. You are asked to estimate the side length of squares formed by dividing this rectangle into two equal-area squares.

Let's break down the solution:

1. Let the width of the rectangle be $w$. Then, the length is $2w$.
2. The area of the rectangle is given by: $\text{Area} = w \times 2w = 2w^2$ We are told that the area of the rectangle is 94 square units, so: $2w^2 = 94$ Solving for $w^2$: $w^2 = \frac{94}{2} = 47$ Therefore: $w = \sqrt{47}$

Since the rectangle is divided into two squares, the side length of each square is $\sqrt{47}$.

Conclusion:

The correct answer is B. Estimate $\sqrt{47}$.

Let me know if you'd like more details, and here are some related questions to explore:

1. What is the approximate value of $\sqrt{47}$?
2. How can we use this method to estimate side lengths for rectangles with other ratios between length and width?
3. What is the side length of each square if the total area was 200 square units?
4. How do the dimensions of the rectangle change if the area is halved?
5. How can you determine the area of one square from a general rectangular area?

Tip: When dealing with square roots, estimating the value by recognizing nearby perfect squares helps with quick approximations.