Show and explain how replacing one equation by the
sum of that equation and a multiple of the other produces
a system with the same solutions as the one shown.
8x + 7y = 39
4x – 14y =-68

Apoll is being conducted at a mall nothingto obtain a sample of the population of an entire country. what is the frame for this type of​ sampling? who would be excluded from the survey and how might this affect the results of the​ survey? what is the frame for this type of​ sampling? a. the frame is people who need new clothes. b. the frame is people who shop at the mall. c. the frame is people who like to shop. d. the frame is the entire population of the country. who would be excluded from the survey and how might this affect the results of the​ survey? a. any person that does not need new clothes is excluded. this could result in sampling bias due to undercoverage. b. any person who does not shop at the mall is excluded. this could result in sampling bias due to undercoverage. c. any person who does not shop at the mall is excluded. this could result in nonresponse bias due to people not participating in the poll. d. there is nobody that is being excluded from the survey.

Consider a= {x|x is alive} f={x|x is in france} m={x|x is a national monument} w{x|x is a woman}. which statements are true regarding elements of the given sets? check all that apply.

Apasta salad was chilled in the refrigerator at 35° f overnight for 9 hours. the temperature of the pasta dish dropped from 86° f to 38° f. what was the average rate of cooling per hour?