Problem
Translate the sentence into an inequality. Twice the difference of a number and 9 is at least -21 . Use the variable $y$ for the unknown number.
Solution
Step 1 ：Translate the sentence into an inequality: 'Twice the difference of a number and 9 is at least -21'. Use the variable y for the unknown number.
Step 2 ：The inequality is \(2*(y - 9) \geq -21\).
Step 3 ：Simplify the inequality using Python code.
Step 4 ：The final answer is \(\boxed{2*(y - 9) \geq -21}\).
