1. **Problem Statement:** Find the area of a figure composed of a rectangle and one semicircle added on the right side, with another semicircle removed on the left side. The rectangle has length 8 and height 4. Both semicircles have radius 4.
2. **Formulae and Important Rules:**
- Area of rectangle: $A_{rect} = \text{length} \times \text{height}$
- Area of a full circle: $A_{circle} = \pi r^2$
- Area of a semicircle: $A_{semi} = \frac{1}{2} \pi r^2$
3. **Calculate the area of the rectangle:**
$$A_{rect} = 8 \times 4 = 32$$
4. **Calculate the area of one semicircle (radius 4):**
$$A_{semi} = \frac{1}{2} \pi (4)^2 = \frac{1}{2} \pi \times 16 = 8\pi$$
5. **Calculate the total area of the figure:**
The figure adds one semicircle on the right and removes one semicircle on the left, so the net semicircle area is:
$$8\pi - 8\pi = 0$$
6. **Final area:**
Since the semicircle added and removed have the same area, they cancel out, so the total area is just the rectangle's area:
$$\boxed{32}$$
7. **Rounding:** The area is exactly 32, so rounded to the nearest tenth is 32.0.
Area Rectangle Semicircle 0E6Fd9
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