Question

1. If A(-1, 1) and B(3,-1) are the endpoints of one side
square ABCD, what is the area of the square?
of
(A) 12
(B) 16
(C) 20
(D) 25
(E) 36

Answer 1

Answer:

C 20

Step-by-step explanation:

we need the distance between both points, then, as this is the side of a square, we square it and get the area of the square.

the distance we get via Pythagoras (the distance is the Hypotenuse of a right-angled triangle with the coordinate differences in x and y being the legs) :

distance² = (-1 -3)² + (1 - -1)² = (-4)² + 2² = 16+4 = 20

distance = sqrt(20)

the area of the square is the side², so again distance², and therefore the area is 20.