Answer:
distance formula; definition of congruence ; if two consecutive sides of a rectangle are congruent, then it's a square
Step-by-step explanation:
Given that RSTU is a rectangle with vertices;
So, using the distance formula;
Reason; distance formula
Since both side RS and ST have the same length, then;
Reason: definition of congruence
So, since two consecutive sides of a rectangle are congruent then;
Reason: if two consecutive sides of a rectangle are congruent, then it's a square