How do you subtract an integer from another integer without using a number line or a counter

Joe has a rectangular chicken coop. the length of the coop is 4 feet less than twice the width. the area of the chicken coop is 510 square feet. what is the length of the chicken coop?

In trapezoid abcd, ac is a diagonal and ∠abc≅∠acd. find ac if the lengths of the bases bc and ad are 12m and 27m respectively.

The owners of four companies competing for a contract are shown in the table below. if a report is released that advocates company b, which of the people having funded the report should result in the most skepticism? company owner of company company a jake adams company b company c company d debby smith henry rose rhonda baker o a. jake adams o b. rhonda baker o c. debby smith o d. henry rose