1. **State the problem:** We are given two points $(-4, r)$ and $(8, 11)$ on a line with slope $\frac{5}{4}$. We need to find the missing coordinate $r$.
2. **Recall the slope formula:** The slope $m$ between two points $(x_1, y_1)$ and $(x_2, y_2)$ is given by
$$m = \frac{y_2 - y_1}{x_2 - x_1}$$
3. **Substitute the known values:** Here, $m = \frac{5}{4}$, $x_1 = -4$, $y_1 = r$, $x_2 = 8$, and $y_2 = 11$. So,
$$\frac{5}{4} = \frac{11 - r}{8 - (-4)}$$
4. **Simplify the denominator:**
$$8 - (-4) = 8 + 4 = 12$$
So the equation becomes
$$\frac{5}{4} = \frac{11 - r}{12}$$
5. **Cross multiply to solve for $r$:**
$$5 \times 12 = 4 \times (11 - r)$$
$$60 = 44 - 4r$$
6. **Isolate $r$:**
$$60 - 44 = -4r$$
$$16 = -4r$$
7. **Divide both sides by $-4$:**
$$\cancel{\frac{16}{-4}} = \cancel{\frac{-4r}{-4}}$$
$$r = -4$$
**Final answer:**
$$\boxed{-4}$$
Find Missing R 72A7C8
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