If given the endpoints of a line segment, is this enough information to write the equation of a circle?

F(x)=x/2-2 and g(x)=2x^2+x-3 find (f+g)(x)

Prove that quadrilateral is a rhombus.

Hurrya vegetable garden and a surrounding path are shaped like a square that together are 11ft wide. the path is 2ft wide if one bag of gravel covers 9 square feet how many bags are needed to cover the path