Question

This is Geometry: In triangle CDE, CD =3y, DE =30, and CE = 45. Determine the range of possible values for y.

Answer 1

one side of a triangle can never be bigger than the sum of the other two.

so CD must be less than 30+45 which is 75

so 3y<75
therefore y<25

Answer 2

Here is a multiple choice A. 15<y<75 B. 45<y<225 C. 30<y<45 D. 5<y<25

Answer 3

oh right, it also cant be less than the difference between the other two sides

because if you think about it, if it was equal to the difference, the tirangle would be a straight line. the same applies for if it was equal to the sum

Anyways, 45-30=5
so the lower bound is 5
5<y<25

Answer 4

Thanks so much