## Sgstudent 2 years ago The perimeter of the triangle with sides 5cm , 6cm and x cm is less than 18cm. Given that the sum of any two of the sides is always greater than the third side, find the range of values of x.

1. syhna

5 + 6 + x < 18 11 + x < 18 x<7 im not quite sure though :)

2. Sgstudent

That's what i did and it's WRONG.

3. syhna

hmmm why?

4. Sgstudent

5. syhna

how'd you get it? i dont seem to understand something about it

6. Sgstudent

Because you and i made the same mistake, we only read the first part of the question and "ignore" the second sentence.

7. itsmylife

5+6+x<18 11+x<18 x<7

8. itsmylife

so it must be 1<x<7

9. itsmylife

@Sgstudent keep rocking

10. Sgstudent

yea it must be 1<x<7

11. Sgstudent

how did we get that?

12. syhna

so 5 +6 > x ??

13. itsmylife

i showed ya up there

14. Sgstudent

why is it 1<x<7 and not x<7 ??

15. itsmylife

sum of three sides is less than 18 5+6+x<18 subtract 11 on both sides x<7 now it cant be 0 or a negative integer

16. syhna

waah i dont get it T.T where'd you get the 1?

17. Sgstudent

same here

18. Sgstudent

where would you get the 1 sir?

19. itsmylife

well look if it will be less than 1 then sum of two sides wont be greater than the third side ;)

20. Sgstudent

that's like trail and error.

21. Sgstudent

nvm if you cant explain how did you got the 1.

22. Sgstudent

23. syhna

i think i understood it already see if the othe side is 1 then 5 + 1 would be equal to 6 right? since we need the third to be greater and not equal to the sum then we use 2 and 2 is greater than 1 so if we would put it in a situation where x = 2 then we'll get 5 + 6 + 2 < 18 13 < 18 5+6 > 2 11 >2 5+2 > 6 7>6 6 + 2 > 5 8 > 5

24. Sgstudent

great :)

25. Sgstudent

We must fulfill the second sentence criteria to find the range of values of x hence, the range would be 1<x<7