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Question
The product of Tanvy’s age (in years) 5 years ago and her age is 8 years later is 30. Find her present age.
Solution
Let the present age of Meena be x years.
According to the question:
`(x-5) (x+8)=30`
⇒`x^2+3x-40=30`
⇒`x^2+3x-70=0`
⇒`x^2+(10-7)x-70=0`
⇒`x^2+10x-7x-70=0`
⇒`x(x+10)-7(x+10)=0`
⇒`(x+10)(x-7)=0`
⇒`x+10=0 or x-7=0`
⇒`x=-10 or x=7`
⇒`x=7`
( ∴Age cannot be negative)
Thus, the present age of Meena is 7 years.
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