• Numerical Ability - Quadratic Equations
Question

I. 2x2- (4 ÷√13)x + 2√13 = 0 

II. (5y2-12)-(9y2-16)=0

  • A) if x > y
  • B) if x ≥  y
  • C) if x < y
  • D) if x ≤ y
  • E) if x = y or relationship cannot be established
Solution

Answer: (b)

Explanation:

2x2 – 4x – √13 x + 2  = 0…(i)

or,2x (x-2)  – √13 (x-2) = 0

or, (x-2) (2x – √13) = 0

x = 2, √13/2

10y2 – 18y – 5√13y +9√13 = 0…(ii)

or,2y (5y-9) – √13 (5y-9) = 0

or,(2y-√13) (5y – 9) = 0

y = 9/5, √13/2

10y2 – 18y – 5√13y + 9 √13 = 0 ……………(ii)

or 2y (5y – 9) – √13 (5y-9) = 0

y = 9/5, √13/2

Hence, x  y.

Answer: (b)

Explanation:

2x2 – 4x – √13 x + 2  = 0…(i)

or,2x (x-2)  – √13 (x-2) = 0

or, (x-2) (2x – √13) = 0

x = 2, √13/2

10y2 – 18y – 5√13y +9√13 = 0…(ii)

or,2y (5y-9) – √13 (5y-9) = 0

or,(2y-√13) (5y – 9) = 0

y = 9/5, √13/2

10y2 – 18y – 5√13y + 9 √13 = 0 ……………(ii)

or 2y (5y – 9) – √13 (5y-9) = 0

y = 9/5, √13/2

Hence, x  y.
Comments