Answer:
12.94 units
Step-by-step explanation:
Perimeter of ∆ABC = AB + BC + AC
✔️Distance between A(1, 1) and B(3, 5):
[tex] AB = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} [/tex]
Where,
[tex] A(1, 1) = (x_1, y_1) [/tex]
[tex] B(3, 5) = (x_2, y_2) [/tex]
[tex] AB = \sqrt{(3 - 1)^2 + (5 - 1)^2} [/tex]
[tex] AB = \sqrt{(2)^2 + (4)^2} [/tex]
[tex] AB = \sqrt{4 + 16} [/tex]
[tex] AB = \sqrt{20} [/tex]
AB = 4.47 units
✔️Distance between B(3, 5) and C(5, 1)
[tex] BC = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} [/tex]
Where,
[tex] B(3, 5) = (x_1, y_1) [/tex]
[tex] C(5, 1) = (x_2, y_2) [/tex]
[tex] BC = \sqrt{(5 - 3)^2 + (1 - 5)^2} [/tex]
[tex] BC = \sqrt{(2)^2 + (-4)^2} [/tex]
[tex] BC = \sqrt{4 + 16} [/tex]
[tex] BC = \sqrt{20} [/tex]
BC = 4.47 units
✔️Distance between A(1, 1) and C(5, 1):
AC = |1 - 5| = 4 units
✅Perimeter of ∆ABC = 4.47 + 4.47 + 4 = 12.94 units