Which graph shows a system of equations with a solution at (–1, 1)?

Step-by-step explanation:

All choices are attached.

Each graph is representing a system of equations which is not linear, because a parabola is not a linear relation.

According to the problem, we have to choose the system which solution is (-1,1). To do so, we just have to observe which graph has an interception point at (-1,1).

You can observe that the second graph has the interception point at (-1,1), that is, both functions has that point in common, because they intercept there.

Therefore, the right answer is the second graph.

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.