Question Number 26352 by sanjib bibhar last updated on 24/Dec/17
$${x}\left({x}+\mathrm{9}\right)=\left({x}+\mathrm{3}\right)\left({x}+\mathrm{7}\right)−\mathrm{10} \\ $$
Answered by jota@ last updated on 24/Dec/17
$$\mathrm{0}={x}+\mathrm{21}−\mathrm{10} \\ $$$${x}=−\mathrm{11}. \\ $$