Find the perimeter of the polygon with vertices in units. Round to the nearest tenth A(8,0), B(-3,2), C(10,2)

Plz explain so I can understand ASAP!!!

With #! i’ve tried to figure it out but i can’t.

What is the product? (x2+3y+7) [yy+1)

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.