SSC CHSL 2022 PYQ — Question 52

The correct answer is option 4 i.e. 40

Given: 

2x + y = 8   .....(i)

xy = 6      .....(ii)

Concept Used: 

(a + b)² = a² + b² + 2ab .....(iii)

Explanation:

Now, taking the square on both sides of equation (i), we get

⇒ (2x + y)² = 64

⇒ 4x² + y² + 4xy = 64    {using equation(iii)}

⇒ 4x² + y² +4(6) = 64

⇒ 4x² + y² = 64 - 24

⇒ 4x² + y² = 40

Hence the required value of 4x² + y² is 40.