Helpp click to see all pls help! what do the mean and a sentence

Step-by-step explanation:

to find the perimeter , need to find the length(distance of the sides)

D=√(x2-x1)²+(y2-y1)²

D between BE and BD and ED

d of BE :

B(1,2) E(5,2)

D of BE = √(5-1)²+(2-2)²=√4²=4

D of BD : (1,2) , (2,4)

D=√(2-1)²+(4-2)² = √1²+2² = √5

ED : (5,2) , (2,4)

d=√(2-5)²+(4-2)²=√-3²+2² =√13

the perimeter= BE+BD+ED