Sizes of envelopes. Rhetoric Advertising is a direct-mail company. It determines that for a particular campaign, it can use any envelope with a fixed width of 3½ in. and an area of at least 17½². Determine (in terms of an inequality) those lengths that will satisfy the company constraints.
We know that the area of rectangle is calculated:A=wl where w-width, l-length and A is an area of a rectangle w=7/2 - fixed 7/2l >=35/2 => l >=35/7 => l >=5 At least means that it’s more then 17 and width is constant.