SOLUTION: determine if DEF with vertices D(6,-6), E(39,-12), and F(24,18) is scalene, isosceles, or equilateral. i tried really hard to figure this out but im not sure if my answer is c

Algebra ->  Triangles -> SOLUTION: determine if DEF with vertices D(6,-6), E(39,-12), and F(24,18) is scalene, isosceles, or equilateral. i tried really hard to figure this out but im not sure if my answer is c      Log On


   

Question 601237: determine if DEF with vertices D(6,-6), E(39,-12), and F(24,18) is
scalene, isosceles, or equilateral.
i tried really hard to figure this out but im not sure if my answer is correct?
Found 2 solutions by jim_thompson5910, mananth:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Go ahead and post your answer along with the problem so we can check it. Also, what distances did you get?

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Find the distance between DE, EF, Df . Then decide the type of triangle
Use distance formula
L(DE)
Distance between two points
x1 y1 x2 y2

6 -6 39 -12
d= sqrt%28%28y2-y1%29%5E2%2B%28x2-x1%29%5E2%29
d=sqrt%28%28-12-%28-6%29%29%5E2%2B%2839%09-6%29%5E2%09%29
d= sqrt%28%28-6%29%5E2%2B%2833%29%5E2%09%29
d= sqrt%28%281125%29%29
l(DE)= 33.54
l(EF)
x1 y1 x2 y2

39 -12 24 18
d=sqrt%28%28y2-y1%29%5E2%2B%28x2-x1%29%5E2%29
d=sqrt%28%2818-%28-12%29%29%5E2%2B%2824%09-39%29%5E2%09%29
d= sqrt%28%2830%29%5E2%2B%28-15%29%5E2%09%29
d= sqrt%28%281125%29++%09%29
d= 33.54
l(EF)
x1 y1 x2 y2

24 18 6 -6
d= sqrt%28%28y2-y1%29%5E2%2B%28x2-x1%29%5E2%29
d=sqrt%28%28-6%28-18%29%29%5E2%2B%286%09-24%29%5E2%29
d= sqrt%28%28-24%29%5E2%2B%28%09-18%29%5E2%09%29
d= sqrt%28%28900%29%29
d= 30.00
Two sides are equal hence aisoscles triangle
m.ananth@hotmail.ca