graph ABCD...is it a square...A(-3,1) B(1,4)C(4,0)D(0,-3) JUSTIFY YOUR ANSWER AND SHOW WORK..THANK YOU

Using the dist. formula:

(AB)^2 = X^2 + Y^2.
(AB)^2 = (1+3)^2 + (4-1)^2 = 16 + 9 = 25
AB = 5.

(BC)^2 = (4-1)^2 + (0-4)^2 = 9 + 16 = 25
BC = 5.

(CD)^2 = (0-4)^2 + (-3-0)^2 = 16 + 9 =25
CD = 5.

(AD)^2 = (1+3)^2 + (-3-0)^2 = 16 + 9 =25
AD = 5.

All sides are equal.