Help please! How do you get x alone: -9 < 3x + 15 < 6.?

remember the goal, x alone means isolate x!
therefore, the first thing to do is subtract 15 to the -9 and the 6. remember, to undo an operation such as addition like 15, you want to perform the opposite operation, in this case, subtraction.

this gives -15-9<3x<6-15

now combine like term, -15-9=-24
3x is 3x
6-15=-9
this gives -24<3x<-9 now we need to divide by three to everything. dividing by three because 3x/3 will isolate x as just x.

so, -24/3 < 3x/3 < -9/3 remember, when you divide or multiply by a negative, the symbols < > will switch!

So, pay close attention, -8 > x > -3. good luck!

- 24 < 3x < - 9

- 8 < x < - 3

x = - 7 , - 6 , - 5 , - 4 ( for x an integer )

-9 < 3x + 15 < 6
-9 - 15 < 3x < 6 - 15
-24 < 3x < -9
-24/3 < x < -9/3
-8 < x < -3

-8 < x < -3

subtracting 15 from each part of the inequality will maintain the inequality. so,
-24< 3x < -9
Also, dividing by positive three will maintain the inequality. So,
-8<x<-3
Or, x is a member of (-8, -3)