Aside of a square bulletin board measures 34 inches. which of these is the closest length of a diagonal?

What is the value of x in the this question ?

Which statement explains how you could use coordinate geometry to prove the opposite sides of a quadrilateral are congruent? a. use the slope formula to prove the slopes of the opposite sides are the same. b. use the slope formula to prove the slopes of the opposite sides are opposite reciprocals. c. use the distance formula to prove the lengths of the opposite sides are the same. d. use the distance formula to prove the midpoints of the opposite sides are the same.

Need plz been trying to do it for a long time and still haven’t succeeded