The above statement means: Twice [the difference of a number and 10] is greater than -23.
Let y be the "number" or the unknown value. In numerical form: 2 × ( y - 10 ) > -23 {Expand the inequality} 2y - 20 > -23 {Make y the subject of inequality. Add 20 on both sides of inequality} 2y > -3 {Divide both sides of inequality by 2} y > -1.5