Mathematics · Straight lines

JEE Main 2026 — 23 January, Evening Shift — Question 4

Let A(1,2)\mathrm{A}(1,2) and C(−3,−6)\mathrm{C}(-3,-6) be two diagonally opposite vertices of a rhombus, whose sides AD an BC are parallel to the line 7x−y=147 \mathrm{x}-\mathrm{y}=14. If B(α,β)\mathrm{B}(\alpha, \beta) and D(γ,δ)\mathrm{D}(\gamma, \delta) are the other two vertices, then ∣α+β+γ+δ∣|\alpha+\beta+\gamma+\delta| is equal to :

  1. Option A:

    9

  2. Option B:

    3

  3. Option C:

    6

    Correct
  4. Option D:

    1

Answer: C

Step-by-step solution

Midpoint of A and C has coordinates (1+(−3)2,2+(−6)2)=(−1,−2)\left(\frac{1+(-3)}{2}, \frac{2+(-6)}{2}\right) = (-1,-2). In a rhombus, diagonals bisect each other, so the midpoint of BD is also (−1,−2)(-1,-2). Thus α+γ2=−1⇒α+γ=−2\frac{\alpha+\gamma}{2} = -1 \Rightarrow \alpha+\gamma = -2 and β+δ2=−2⇒β+δ=−4\frac{\beta+\delta}{2} = -2 \Rightarrow \beta+\delta = -4. Hence α+β+γ+δ=(−2)+(−4)=−6\alpha+\beta+\gamma+\delta = (-2)+(-4) = -6. Therefore ∣α+β+γ+δ∣=6|\alpha+\beta+\gamma+\delta| = 6.

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Mathematics
Chapter
Straight lines
Topic
Pair of Straight Lines
Let A (1,2) and C (-3,-6) be two diagonally opposite vertices of a… | JEE Main 2026 PYQ with Solution · DhiX AI