1. **State the problem:** We need to find the value of $\cos L$ in a right triangle $\triangle LMN$ where the right angle is at vertex $M$. The side opposite angle $L$ is $MN = 4$, and the hypotenuse $LN = 8$.
2. **Recall the definition of cosine in a right triangle:**
$$\cos L = \frac{\text{adjacent side to } L}{\text{hypotenuse}}$$
3. **Identify the adjacent side to angle $L$:** Since $MN$ is opposite $L$ and $LN$ is the hypotenuse, the remaining side $LM$ is adjacent to $L$. We need to find $LM$ using the Pythagorean theorem:
$$LM = \sqrt{LN^2 - MN^2} = \sqrt{8^2 - 4^2} = \sqrt{64 - 16} = \sqrt{48}$$
4. **Simplify $\sqrt{48}$:**
$$\sqrt{48} = \sqrt{16 \times 3} = 4\sqrt{3}$$
5. **Calculate $\cos L$:**
$$\cos L = \frac{LM}{LN} = \frac{4\sqrt{3}}{8} = \frac{\cancel{4}\sqrt{3}}{\cancel{8}2} = \frac{\sqrt{3}}{2}$$
6. **Evaluate the decimal value:**
$$\cos L \approx \frac{1.732}{2} = 0.866$$
7. **Round to the nearest hundredth:**
$$\cos L \approx 0.87$$
**Final answer:** $\boxed{0.87}$
Cosine Value 2D89Ee
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