1. **Problem:** Given a rectangle with diagonal $c=13$ cm and height $h=8$ cm, find the area $A$.
2. **Formula:** For a rectangle, area $A = \text{length} \times \text{height}$. The diagonal relates length $l$ and height $h$ by the Pythagorean theorem: $$c^2 = l^2 + h^2$$
3. **Step 1:** Use the Pythagorean theorem to find length $l$:
$$13^2 = l^2 + 8^2$$
$$169 = l^2 + 64$$
$$l^2 = 169 - 64 = 105$$
$$l = \sqrt{105}$$
4. **Step 2:** Calculate the area:
$$A = l \times h = \sqrt{105} \times 8 = 8\sqrt{105}$$
5. **Step 3:** Approximate the area:
$$\sqrt{105} \approx 10.247$$
$$A \approx 8 \times 10.247 = 81.976$$ cm$^2$
**Final answer:** The area of the rectangle is approximately $81.98$ cm$^2$.
Rectangle Area 2E08B0
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