Question

Length of common chord of the parabolas $x^2=4y$ and $y^2=4x$ is

• A. 4
• B. $4\sqrt{3}$
• C. $4\sqrt{2}$
• D. 2

Answer 1

Answer: (C)

Points of intersection of $x^2=4y$ and $y^2=4x$ are $(0,0)$ and $(4,4)$
$\Rightarrow$ Length of common chord $=4\sqrt{2}$