An area of 24 square feet and height 3 3/4

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

Which expression is equivalent to? assume x > 0 and y > 0.

Which expression is equivalent to 2x^2+7x+4?