5.1. Construct a rectangle, where each side is greater than 1, using six rectangles $7 \times 1, 6 \times 1, 5 \times 1, 4 \times 1, 3 \times 1, 2 \times 1$ and a square $1 \times 1$.
Solution. From a rectangle $6 \times 1$ and a square $1 \times 1$, we form a rectangle $7 \times 1$. Similarly, we form rectangles $7 \times 1$ from pairs of rectangles $5 \times 1, 2 \times 1$ and $4 \times 1, 3 \times 1$. From the four resulting rectangles $7 \times 1$, a rectangle $7 \times 4$ is formed.