Mirror image of a point in a line with unknowns in the point or the image: find them
The same question, asked 3 times: 2021 Paper 2*, 22 Jan 2026 S1*, 4 Apr 2026 S2. Every wording below, oldest first.
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Question 1
2021 Paper 2
61Let a,b∈R. If the mirror image of the point P(a,6,9) with respect to the line 7x−3=5y−2=−9z−1 is (20,b,−a−9), then ∣a+b∣ is equal to:
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Question 2
22 Jan 2026 S1
61If the image of the point P(1,2,a) in the line 3x−6=2y−7=27−z is Q(5, b,c), then a2+b2+c2 is equal to
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Question 3
4 Apr 2026 S2
64If (2α+1,α2−3α,2α−1) is the image of (α,2α,1) in the line 3x−2=2y−1=1z, then the possible value(s) of α is(are) :
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