Final answer:
To find the missing coordinate r, we can use the slope formula and the given points (-4, r) and (-1, 5). Cross multiplying the equation -1 = (5 - r) / 3 helps us solve for r, and we find that r = 8.
Step-by-step explanation:
To find the missing coordinate r, we can use the slope formula: slope = (y2 - y1) / (x2 - x1).
Using the points (-4, r) and (-1, 5), we have: -1 = (5 - r) / (-1 - (-4)).
Simplifying the equation gives us -1 = (5 - r) / 3. We can cross multiply to solve for r: -1 * 3 = 5 - r, which simplifies to -3 = 5 - r. We can then solve for r: r = 5 + 3, which gives us r = 8. Therefore, the missing coordinate r is 8.
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