Write the rules for factoring. x method, difference of squares

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.

What percent of the circle below is shaded?

Which coefficient matrix represents a system of linear equations that has a unique solution ? options in photo*