1. **State the problem:** We need to find side $g$ (EF) in triangle EGF where angle $G = 101^\circ$, side $EG = 5$, and side $GF = 4$.
2. **Formula used:** The Law of Cosines states:
$$g^2 = EG^2 + GF^2 - 2 \times EG \times GF \times \cos(G)$$
This formula relates the lengths of sides of a triangle to the cosine of one of its angles.
3. **Substitute known values:**
$$g^2 = 5^2 + 4^2 - 2 \times 5 \times 4 \times \cos(101^\circ)$$
4. **Calculate each term:**
$$g^2 = 25 + 16 - 40 \times \cos(101^\circ)$$
5. **Evaluate $\cos(101^\circ)$:**
Since $101^\circ$ is obtuse, $\cos(101^\circ)$ is negative. Using a calculator:
$$\cos(101^\circ) \approx -0.1908$$
6. **Plug in the cosine value:**
$$g^2 = 25 + 16 - 40 \times (-0.1908)$$
$$g^2 = 41 + 7.632$$
$$g^2 = 48.632$$
7. **Find $g$ by taking the square root:**
$$g = \sqrt{48.632} \approx 6.97$$
8. **Round to the nearest tenth:**
$$g \approx 7.0$$
**Final answer:**
$$\boxed{7.0}$$
Law Of Cosines 33B790
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