*"<_" is less than equal to*

5) -15<x-8<-4

6)12<_4n<28

7)-2<_3b+7<_13

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

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?

To solve inequalities such as these, we'll follow a similar process. Let's break it down step-by-step for each inequality:

5) -15 < x-8 < -4

First, let's isolate the variable by adding 8 to all sides of the inequality:

-15 + 8 < x-8 + 8 < -4 + 8

Simplifying further, we get:

-7 < x < 4

So the solution to the inequality is x lies between -7 and 4, not including these endpoints.

6) 12 <= 4n < 28

To solve this inequality, we'll divide both sides of the inequality by 4:

12/4 <= 4n/4 < 28/4

This simplifies to:

3 <= n < 7

Therefore, n lies between 3 and 7, including 3 but not including 7.

7) -2 <= 3b + 7 <= 13

First, let's isolate the variable by subtracting 7 from all sides of the inequality:

-2 - 7 <= 3b + 7 - 7 <= 13 - 7

This simplifies to:

-9 <= 3b <= 6

Next, let's divide all sides of the inequality by 3:

-9/3 <= 3b/3 <= 6/3

This further simplifies to:

-3 <= b <= 2

So the solution to the inequality is b lying between -3 and 2, including both endpoints.