Let x represent some number.
The phrase "eight times some number" can be expressed as 8x. If that quantity is increased by 9, we can represent it as 8x+9. If that expression is equal to -10, then we can write down the equation 8x+9=-10.
Therefore, the phrase "eight times some number increased by 9 is -10" can be written using algebraic languaje as:
[tex]8x+9=-10[/tex]