I'm supposed to find the distance between 1,2 and -2,-2 someone

d = sqrt.[(x1 - x2)^2 + (y1 - y2)^2]
given (1,2) and (-2,-2)
plug in the given
d = sqrt.[(1 - -2)^2 + (2 - -2)^2]
minus a negative is the same thing as adding a positive
d = sqrt.[(1 + +2)^2 + (2 + +2)^2]
d = sqrt.[(3)^2 + (4)^2]
d = sqrt.[9 + 16]
d = sqrt.[25]
d = 5

Hope this helps