JEE MAIN - Mathematics (2025 - 4th April Evening Shift - No. 9)
Let for two distinct values of p the lines $y=x+\mathrm{p}$ touch the ellipse $\mathrm{E}: \frac{x^2}{4^2}+\frac{y^2}{3^2}=1$ at the points A and B . Let the line $y=x$ intersect E at the points C and D . Then the area of the quadrilateral $A B C D$ is equal to :
48
20
24
36
Explanation
$E: \frac{x^2}{4^2}+\frac{y^2}{3^2}=1$
$$\begin{aligned} & T: y=m x \pm \sqrt{16 m^2+9} \\ & y=x+p \\ & \Rightarrow m=1 \\ & \Rightarrow p= \pm \sqrt{16+9} \\ & = \pm 5 \end{aligned}$$
$T: y=x \pm 5$ will to cut the $E$ at $A\left(-\frac{16}{5}, \frac{9}{5}\right)$
$$B\left(\frac{16}{5},-\frac{9}{5}\right)$$
Also, $y=x$ will cut the $E$ at $C\left(\frac{12}{5}, \frac{12}{5}\right)$
$$D\left(-\frac{12}{5},-\frac{12}{5}\right)$$
$A B C D$ in not give in cyclic order
$\therefore$ it does not form any quadrilateral
$\therefore \quad$ No option should match
If order is not considered then
Area $=24$ sq. unit.
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