Question

The product of Ramu's age (in yeras) five years ago and his age (in years) nine years later is $15$. Ramu's present age is ------yrs.

Answer 1

$\Rightarrow$ Let Ramu's present age be $xyears$.

According to the question,

$\Rightarrow$ $(x-5)(x+9)=15$

$\Rightarrow$ $x^2+9x-5x-45-15=0$

$\Rightarrow$ $x^2+4x-60=0$

$\Rightarrow$ $x^2+10x-6x-60=0$

$\Rightarrow$ $x(x+10)-6(x+10)=0$

$\Rightarrow$ $(x+10)(x-6)=0$

$\Rightarrow$ $x+10=0$ and $x-6=0$

$\Rightarrow$ $x=-10$ and $x=6$

$\Rightarrow$ Age cannot be negative.

$\therefore$ Ramu's present age is $6$ years.