Answer:
17.19 units.
Explanation:
First calculate the distance between the 3 points to get the lengths of sides of the triangle.
Side AC = sqrt( (3-5)^2 + (4- -4)^2) = sqrt68
Side AT = sqrt((5-2)^2 + (-4-2)^2 = sqrt45
Side CT = sqrt((3-2)^2 + (4-2)^2) = sqrt5
So the perimeter = sqrt68 + sqrt45 + sqrt5
= 17.19 units.