1. **State the problem:** We have a triangle with sides labeled $r$, 17, and 5, and an angle of $32^\circ$ opposite side $r$. We need to find the length of side $r$.
2. **Identify the formula:** We can use the Law of Cosines, which states:
$$c^2 = a^2 + b^2 - 2ab\cos(C)$$
where $c$ is the side opposite angle $C$.
3. **Assign values:** Let $r = c$, $a = 17$, $b = 5$, and $C = 32^\circ$.
4. **Apply the Law of Cosines:**
$$r^2 = 17^2 + 5^2 - 2 \times 17 \times 5 \times \cos(32^\circ)$$
5. **Calculate each term:**
$$17^2 = 289$$
$$5^2 = 25$$
$$2 \times 17 \times 5 = 170$$
6. **Calculate cosine:**
$$\cos(32^\circ) \approx 0.8480$$
7. **Substitute and simplify:**
$$r^2 = 289 + 25 - 170 \times 0.8480$$
$$r^2 = 314 - 144.16$$
$$r^2 = 169.84$$
8. **Find $r$ by taking the square root:**
$$r = \sqrt{169.84} \approx 13.0$$
**Final answer:**
$$r \approx 13.0$$
Find R A21E6D
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