Concept:If a line lies in a plane, its direction vector is perpendicular to the plane's normal, and every point on the line satisfies the plane equation.
Explanation:The direction ratios of the line are
(2,−1,2).
The direction ratios of the normal to the plane are
(α,3,−1).
Since the line lies in the plane, the dot product of these direction vectors is zero.
2α+(−1)(3)+2(−1)=02α−3−2=02α=5⇒α=25The point
(3,−5,−2) lies on the line, so it also lies on the plane.
Substitute this point into the plane equation:
25(3)+3(−5)−(−2)+β=0215−15+2+β=0215−13+β=0β=211Answer:α=25,
β=211; hence the correct option is D.