How to write “the difference of x and the square of x increased by 7” into an algebraic expression?

Write the inverse of the logarithmic function used to represent the situation in model 1, f(x)=3+2in x . express the answer in radical form.

Really need on these. i have no idea what to do

Jack lives on a farm and has a large backyard. the area of his rectangular backyard is of a square mile. if the width of the yard is of a mile, what fraction of a mile is the length of the rectangular backyard?