What represents "the average of 171 and x" ?

You can model the population of a certain city between 1955-2000 by the radical function p(x)=55,000 sqrt x-1945. using this model, in which year was the population of that city 220,000

For each proportion find the unknown number x 1/5/8=×/15

Find the number of real number solutions for the equation. x2 + 5x + 7 = 0 0 cannot be determined 1 2