What is the distance (0 -1) (-1 1)?

Question

http://www.purplemath.com/modules/distform.htm the distance formula

Answer 1

X-scale distance = 1

Y-scale distance = 2

We can form a right triangle from the two points.

(a^2) + (b^2) = c^2

(1^2) + (2^2) = c^2

1 + 4 = c^2

c = square root [5]

c = 2.236