Tran says that -1/4×-7+9/4×+2× is equivalent to 4×-7. how can substituting any value for × you determine whether tran is correct ? is tran correct ? use substituion to justify your answer

Which system of linear inequalities is represented by the graph?

What is the interquartile range of this data set? 2, 5, 9, 11, 18, 30, 42, 48, 55, 73, 81

Suppose you are choosing a 6-digit personal access code. this code is made up of 4 digits chosen from 1 to 9, followed by 2 letters chosen from a to z. any of these digits or letters can be repeated. find the total number of personal access codes that can be formed. 492,804 341,172 39,917,124 4,435,236