Q5 of 51 Page 42

If Zeba were younger by 5 years than what she really is, then the square of her age (in years) would have been 11 more than five times her actual age, what is her age now?

Let Zeba’s present age be x.

According to question,


⇒ (x - 5)2 = 5x + 11


⇒ x2 - 10x + 25 = 5x + 11


∴ x2 - 15x + 14 = 0


By using the quadratic formula,






∴ Zeba’s age is 14. (* x – 5 = -4 and age cannot be negative.)


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