Just for you beautiful!
Use distance formula: d = sqrt((x2 - x1)^2 + (y2 - y1)^2)
(11,-4) is (x1,y1) and (-12,-4) is (x2,y2)
Plug in and simplify
d = sqrt((-12 - 11)^2 + (-4 - -4)^2)
d = sqrt((-23)^2 + (0)^2)
d = sqrt(529 + 0)
d = sqrt(529)
d = 23 (positive because length cannot be negative) ;)
