The total of 11 and half of x gives 15

how would this be turned into a two-step equation?

What is the smallest integer n such that n\sqrt{2} is greater than 20

The head librarian at the library of congress has asked her assistant for an interval estimate of the mean number of books checked out each day. the assistant provides the following interval estimate: from 740 to 920 books per day. what is an efficient, unbiased point estimate of the number of books checked out each day at the library of congress?

Solve the given system of equations. 2y= -x+9 , 3x-6= -15