In △ACD, if AC≅AD, m∠A = 3x − 4, m∠C = 5x + 1, and m∠D = 7x − 27, find x and the measure of each angle.

x = 14

m∠A = 38°

m∠C = 71°

m∠D = 71°

Step-by-step explanation:

By the property of a triangle,

"Sum of interior angles of a triangle is 180°"

m∠A + m∠C + m∠D = 180°

By substituting the values of the angles given in the question,

(3x - 4)° + (5x + 1)° + (7x - 27)° = 180°

(3x + 5x + 7x) + (-4 + 1 - 27) = 180

15x - 30 = 180

15x = 210

x = 14

Therefore, m∠A = 3x - 4

                           = 3(14) - 4

                           = 38°

m∠C = 5x + 1

        = 5(14) + 1

        = 71°

m∠D = 7x - 27

         = 7(14) - 27

         = 98 - 27

         = 71°

452,489 to the nearest thousand is 452,000

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.