David typically takes 3 less hours than Marilyn to build a shelf if each works alone. David and Marilyn worked together to build a shelf for 1 hour, and then Marilyn finished the job without David after an additional 3 hours. How long would it have taken David to build the shelf alone? Do not include the units in your answer.

Does anyone know of a quizlet or something for edmentrum /plato algebra 1

You work for a lender that requires a 20% down payment and uses the standard depth to income ratio to determine a person‘s a little eligibility for a home loan of the following choose the person that you would rate the highest on their eligibility for a home loan

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.