Answer:
34 [units].
Step-by-step explanation:
1) according to the property of parallelogram (AC=BD and AB=CD) the required perimeter can be calculated as P=2AB+2AC;
2) the length of AB=7 (the coordinates 'y' are equal);
3) the length of AC:
[tex]|AC|=\sqrt{(1+5)^2+(-2-6)^2}=10.[/tex]
4) finally, the required perimeter is:
P=2(7+10)=34 [units].
