Answer:
Step-by-step explanation:
[tex]Distance=\sqrt{(x_2-x_1)^{2}+(y_2-y_1)^{2}}\\\\AB=\sqrt{(4-1)^{2}+(6-2)^{2}}=\sqrt{(3)^{2}+(4)^{2}} =\sqrt{9+16}=\sqrt{25}=5\\\\AC=\sqrt{(4-1)^{2}+(2-2)^{2}}=\sqrt{(3)^{2}}=3\\\\BC=\sqrt{(4-4)^{2}+(6-2)^{2}}=\sqrt{(4)^{2}}=4\\[/tex]
Perimeter = AB + AC + BC = 5 + 3 + 4 = 12
