1. **State the problem:** Find the surface area of a square pyramid with base side length $1$ ft and slant height $5$ ft.
2. **Formula:** The surface area $A$ of a square pyramid is given by:
$$A = B + L$$
where $B$ is the area of the square base and $L$ is the lateral surface area.
3. **Calculate base area:** Since the base is a square with side length $s=1$ ft,
$$B = s^2 = 1^2 = 1 \text{ ft}^2$$
4. **Calculate lateral area:** The lateral area is the sum of the areas of the four triangular faces. Each triangle has base $s=1$ ft and height equal to the slant height $l=5$ ft.
Area of one triangle:
$$\frac{1}{2} \times s \times l = \frac{1}{2} \times 1 \times 5 = \frac{5}{2} = 2.5 \text{ ft}^2$$
Since there are 4 triangles:
$$L = 4 \times 2.5 = 10 \text{ ft}^2$$
5. **Total surface area:**
$$A = B + L = 1 + 10 = 11 \text{ ft}^2$$
**Final answer:** The surface area of the square pyramid is $11$ ft².
Square Pyramid Area A370F9
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