Posted by Jessie on .
Which three lengths cannot be the lengths of the sides of a triangle?
A)25 m, 16 m, 10 m
B)15 m, 13 m, 12 m
C)18 m, 5 m, 10 m
D)8 m, 8 m, 15 m

Geometry 
Reiny,
to form a triangle , the sum of any two lengths must be greater than the third length.
Look at C)
18+5> 10 ? , yes
18 + 10 > 5 ? , yes
5+10 > 18 ? , NO
the 3 sides cannot form a triangle
test the others the same way 
Geometry 
A. Nony Mous,
thanks so much!!! it worked. all are bigger than the third length except for c. :)