Answer:
(c) pn = 70
Step-by-step explanation:
If k is the point of intersection of the diagonals, then ...
pk = kn
5x = x^2 -14
x^2 -5x -14 = 0 . . . . subtract 5x
(x -7)(x +2) = 0 . . . . factor
The positive solution is x = 7.
pk = 5x = 5·7 = 35 . . . . pn is twice as long.
pn = 70
