hihihihihihi548 hihihihihihi548 16-06-2021 Mathematics contestada Abdallah noticed that if he takes the opposite of his age and adds 40, he gets the number 28. Ali wants to know Abdallah's age. He wrote the equation -x + 40 = 28 And he got his age as 68. What was Ali's mistake? how old is Abdallah? Please solve neatly and show steps.