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The distance of the point $$(-1, 9, -16)$$ from the plane $$2x + 3y - z = 5$$ measured parallel to the line $$\frac{x+4}{3} = \frac{2-y}{4} = \frac{z-3}{12}$$ is
We need to find the distance from $$(-1, 9, -16)$$ to the plane $$2x + 3y - z = 5$$, measured parallel to the line $$\frac{x+4}{3} = \frac{2-y}{4} = \frac{z-3}{12}$$.
Next, the direction ratios of the given line are $$(3, -4, 12)$$.
We then write the parametric equations of the line passing through $$(-1, 9, -16)$$ with direction ratios $$(3, -4, 12)$$:
$$x = -1 + 3t, \quad y = 9 - 4t, \quad z = -16 + 12t$$
Substituting these into the plane equation $$2x + 3y - z = 5$$ gives:
$$2(-1 + 3t) + 3(9 - 4t) - (-16 + 12t) = 5$$
$$-2 + 6t + 27 - 12t + 16 - 12t = 5$$
$$41 - 18t = 5$$
$$18t = 36$$
$$t = 2$$
At $$t = 2$$, the intersection point is
$$ (x, y, z) = (-1 + 6, 9 - 8, -16 + 24) = (5, 1, 8)$$
Finally, the distance between $$(-1, 9, -16)$$ and $$(5, 1, 8)$$ is
$$d = \sqrt{(5+1)^2 + (1-9)^2 + (8+16)^2} = \sqrt{36 + 64 + 576} = \sqrt{676} = 26.$$
Thus, the required distance is 26.
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