For this case we have that by definition, the distance between two points is given by:
[tex]d = \sqrt {(x_ {2} -x_ {1}) ^ 2+ (y_ {2} -y_ {1}) ^ 2}\\(x_ {1}, y_ {1}) :( 2,2)\\(x_ {2}, y_ {2}) :( 5,5)[/tex]
Substituting the points:
[tex]d = \sqrt {(5-2) ^ 2 + (5-2) ^ 2}\\d = \sqrt {(3) ^ 2 + (3) ^ 2}\\d = \sqrt {9 + 9}\\d = \sqrt {18}\\d = 3 \sqrt {2}[/tex]
ANswer:
[tex]d = 3 \sqrt {2}[/tex]
