1. **State the problem:** We have a triangle with sides 70, 52, and 48 units. We want to find the angle $x$ opposite the side of length 70.
2. **Formula used:** The Law of Cosines states:
$$c^2 = a^2 + b^2 - 2ab \cos(C)$$
where $c$ is the side opposite angle $C$.
3. **Apply the formula:** Here, $c=70$, $a=52$, $b=48$, and $C=x$.
$$70^2 = 52^2 + 48^2 - 2 \times 52 \times 48 \times \cos(x)$$
4. **Calculate squares:**
$$4900 = 2704 + 2304 - 4992 \cos(x)$$
5. **Simplify the right side:**
$$4900 = 5008 - 4992 \cos(x)$$
6. **Isolate the cosine term:**
$$4900 - 5008 = -4992 \cos(x)$$
$$-108 = -4992 \cos(x)$$
7. **Divide both sides by -4992:**
$$\cancel{-108} \div \cancel{-4992} = \cos(x)$$
$$\cos(x) = \frac{108}{4992}$$
8. **Simplify the fraction:**
$$\cos(x) = \frac{9}{416} \approx 0.02163$$
9. **Find the angle $x$ using inverse cosine:**
$$x = \cos^{-1}(0.02163) \approx 88.8^\circ$$
**Final answer:** $x \approx 88.8^\circ$ (nearest tenth)
This corresponds to choice C.
Law Cosines Angle 8Da2B7
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