Question:
There are three consecutive integers such that the square of the first increased by the product of the other two gives 154. What are the integers?
Solution:
Let three consecutive integer be $x,(x+1)$ and $(x+2)$
Then according to question
$x^{2}+(x+1)(x+2)=154$
$x^{2}+x^{2}+3 x+2=154$
$2 x^{2}+3 x+2-154=0$
$2 x^{2}+3 x-152=0$
$2 x^{2}+3 x-152=0$
$2 x^{2}-16 x+19 x-152=0$
$2 x(x-8)+19(x-8)=0$
$(x-8)(2 x+19)=0$
$(x-8)=0$
$x=8$
Or
$(2 x+19)=0$
$x=\frac{-19}{2}$
Since, x being a positive number, so x cannot be negative.
Therefore,
$x+1=8+1$
$=9$
And
$x+2=8+2$
$=10$
Thus, three consecutive positive integer be $8,9,10$