Question

*"<_" is less than equal to*

5) -15<x-8<-4

6)12<_4n<28

7)-2<_3b+7<_13

Answer 1

for "less than or equal to" use the left carat key "<" along with the "alt option" key to get "≤".

Answer 2

just solve both sides at once.

-15<x-8<-4
add 8 everywhere:
-15+8 < x-8+8 < -4+8
-7 < x < 4

what do you get for the others?