3|2x-5|> 21 brainliest solve for x

  (x < -1) ∪ (6 < x)

Step-by-step explanation:

Divide by 3

  |2x -5| > 7

"Unfold." That is, put the negative of the constant value on the other side of the absolute value expression, using the same inequality symbol.

  -7 > 2x -5 > 7 . . . . . . . . . . this notation is convenient for expressing the two disjoint inequalities, but is not strictly correct because it is not true that -7 > 7.

Add 5, then divide by 2

  -2 > 2x > 12

  -1 > x > 6 . . . . . . . . . . this should be interpreted as -1 > x OR x > 6. Usually a compound inequality is interpreted as having an AND connector.

The solution is ...

  (x < -1) ∪ (6 < x)

_____

The more correct (and less convenient) way to "unfold" the absolute value is to write it as two distinct inequalities:

Each of these is then separately solved (by adding 5 and dividing by 2) to get ...

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.