1. **Problem Statement:**
Find the measure of angle $\angle I$ in triangle $\triangle IJK$ where sides $i=96$ cm, $j=22$ cm, and $k=85$ cm.
2. **Formula Used:**
We use the Law of Cosines to find an angle when all three sides are known:
$$\cos(\angle I) = \frac{j^2 + k^2 - i^2}{2jk}$$
3. **Substitute the known values:**
$$\cos(\angle I) = \frac{22^2 + 85^2 - 96^2}{2 \times 22 \times 85}$$
4. **Calculate the squares:**
$$22^2 = 484, \quad 85^2 = 7225, \quad 96^2 = 9216$$
5. **Plug in the values:**
$$\cos(\angle I) = \frac{484 + 7225 - 9216}{2 \times 22 \times 85} = \frac{7709 - 9216}{3740} = \frac{-1507}{3740}$$
6. **Simplify the fraction:**
$$\cos(\angle I) = -\frac{1507}{3740}$$
7. **Calculate the cosine value:**
$$\cos(\angle I) \approx -0.4029$$
8. **Find the angle using inverse cosine:**
$$\angle I = \cos^{-1}(-0.4029)$$
9. **Calculate the angle in degrees:**
$$\angle I \approx 114.7^\circ$$
**Final answer:** The measure of $\angle I$ is approximately **114.7 degrees** to the nearest tenth.
Law Cosines Angle F73Aaa
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