Talia is writing a coordinate proof to show that the diagonals of a square are perpendicular. she begins by assigning coordinates to the vertices of a square as shown.

which sentence describes what talia should do to show that the diagonals of the square are perpendicular?

a) show that sq=pr=a(sqr rt)2

b) show that the midpoint of line sq is the same as the midpoint of line pr

c) show that the slope of line sq is 1 and the slope of line pr is -1

d) show that line sq is and line pr intersect at (a/2, a2)