Question

A triangle has two sides that measure 12 meters and 3 meters. Which could be the measure of the third side?

A. 17 m
B. 15 m
C. 10 m
D. 9 m

Answer 1

ok, let a=12, b= 3, 3rd side =c

since one side of a triangle CANNOT be greater than sum of other 2 sides, we have

a+b< c .... a+c<b ....b+c<a

got this ?

Answer 2

that will give you range of 'c'

Answer 3

okay thanks

Answer 4

so, what u got as answer ?

Answer 5

is it either c or d

Answer 6

yeah, that comes from c<15

a+c<b ----> 12+c<3 ---->> c<-9 (obvious because length must be positive)
b+c<a ----> 3+c < 12 ---->> c< 9
so it cannot be 9

Answer 7

got it @arlira ?