what is an example of a situation that you might be able to use an equation with a single unknown to understand

What is the solution of the systems of equations? y=2/3x+3 x=-2

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e.g. 98.76543).

There are 85 apples on the big tree, john picked out 15%. how many did john pick out?