Which of the following functions
opens downward?
y = –2x2 + x + 3
f(x) = 0.5x2 – x.- 1

Which expression gives you the distance between the points (5,1)and(9,-6)

Quadrilateral abcd in the figure below represents a scaled-down model of a walkway around a historic site. quadrilateral efgh represents the actual walkway. abcd is similar to efgh. what is the total length, in feet of the actual walkway?

Find the distance between (0,5) & (-4,2)