Basically we have this one problem on homework where it goes "Find the perimeter of the figure" and the coordinates are F=(8,4) D=(5,1) and E= (6,6) So how do I work this problem out? I tried twice to find the distance between all by using the distance formula for lines DE, EF, and FD. There is a cheat cheat in our math textbook because we have the whole entire thing on our school computers, but I use it to check my work. I have been getting the perimeter as 12.1 units but the answer key says 36.2 units? How am I to work the problem out? I use D=(X(2)-X(1))Squared + (Y(2)-Y(1))Squared and then D=the square root of the answer. Its a bit confusing because I cannot use the special characters in answers, but I hope you know what I mean. Anyway, please explain what I am doing wrong?
My answers were
Line FD=4.2 (nearest tenth)
Line DE=5.2 (Nearest tenth)
Line EF= 2.8 (Nearest tenth)
and added up I get perimeter=12.2
Thanks in advanced
My answers were
Line FD=4.2 (nearest tenth)
Line DE=5.2 (Nearest tenth)
Line EF= 2.8 (Nearest tenth)
and added up I get perimeter=12.2
Thanks in advanced
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I'd say that the answer key is wrong. You're calculating the lengths correctly.
The distance FD is the square root of the sum of the squares of the x and y differences:
Side FD:
x change = 3 (from 8 to 5)
y change = 3 (from 4 to 1)
distance = sqrt(3^2 + 3^2) = sqrt(9 + 9) = sqrt(18) = 4.2
The distance FD is the square root of the sum of the squares of the x and y differences:
Side FD:
x change = 3 (from 8 to 5)
y change = 3 (from 4 to 1)
distance = sqrt(3^2 + 3^2) = sqrt(9 + 9) = sqrt(18) = 4.2