Q10 of 83 Page 90

If the age of Sachin 8 year ago is multiplied by his age two years later, the result is 1200. Find the age of Sachin at present.

Let present age of Sachin be x yrs.

∴ 8 yrs ago, his age was = (x – 8) yrs.


And, 2 yrs later his age will be = (x + 2) yrs.


⇒ (x – 8)(x + 2) = 1200


⇒ x2 – 6x – 16 = 1200


⇒ x2 – 6x – 1216 = 0


⇒ x2 – (38 – 32)x – 1216 = 0


⇒ x2 – 38x + 32x – 1216 = 0


⇒ x(x – 38) + 32(x – 38) = 0


⇒ (x – 38) + (x + 32) = 0


⇒ x – 38 = 0 or x + 32 = 0


⇒ x = 38 or x = – 32


But age cannot be negative.


⇒ x = 38 years.


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