Subtract 9 from both sides: We have the equation −99=9x+9. To isolate the term containing x, we need to subtract 9 from both sides of the equation.Calculation: −99−9=9x+9−9
Simplify both sides: Simplify both sides of the equation.Calculation: −108=9x
Divide by 9: To solve for x, divide both sides of the equation by 9.Calculation: −108/9=9x/9
Find value of x: Simplify the equation to find the value of x.Calculation: −12=x