Please class is today and i still have all of my hw to i have no idea, be quick so much! given: △abc is equilateral. the radius of each circle is r. find: ab in terms of "r"

Jack has a rectangular piece of land, the area of which is represented by a1 = 9.5l. his brother has a different rectangular piece of land, the area of which is represented by a2 = l(14 − l). let a represent the area in square meters and l represent the length in meters of the pieces of land. the two equations plotted on a graph meet at a point as shown in the image