Which is a translation of "two times the difference of a number and 7"

News cameras take an overhead picture of a crowd at an outdoor event journalist then count the total number of people in the picture and use the sample of estimate the total number of people in the crowd this process is an example of

This question awards 100 ! i really don’t want to fail i will also mark you !

What is the solution set of the quadratic inequality x^2-5< or equal to 0