Final answer:
To find the perimeter of the red triangle, use the distance formula to find the lengths of the sides AB, AC, and BC. Then, add the lengths of the sides to find the perimeter is 35.68.
Step-by-step explanation:
To find the perimeter of the red triangle, we need to find the lengths of its sides. We can use the distance formula to find the lengths of AB, AC, and BC.
AB = √[(x2 - x1)^2 + (y2 - y1)^2] = √[(2 - 8)^2 + (-5 - 6)^2] = √[36 + 121] = √157
AC = √[(x2 - x1)^2 + (y2 - y1)^2] = √[(-5 - 8)^2 + (1 - 6)^2] = √[169 + 25] = √194
BC = √[(x2 - x1)^2 + (y2 - y1)^2] = √[(2 - (-5))^2 + (-5 - 1)^2] = √[49 + 36] = √85
Now, we can add the lengths of the sides to find the perimeter: AB + AC + BC = √157 + √194 + √85 = (12.53 + 13.93 + 9.22) = 35.68