What three different equations that have x = 5 as a solution

What are the values of each variable in the diagram below?

The sum of the first eight terms of an arithmetic progression is 9m + 14. the fifth term of the06 progression is 2m - 6, where m is a constant.given that the first term of the progression is 26,find the value of the common difference, d and thevalue of m.

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.